English words starting with X

x chromosome

1. noun: the sex chromosome that is present in both sexes: singly in males and doubly in females; "human females normally have two X chromosomes"

x ray

1. noun: electromagnetic radiation of short wavelength produced when high-speed electrons strike a solid target
2. noun: a radiogram made by exposing photographic film to X rays; used in medical diagnosis

x-axis

1. noun: the horizontal axis in a plane coordinate system

x-linked

1. adjective: relating to genes or characteristics or conditions carried on the X chromosome; "an X-linked mutation"

x-linked dominant inheritance

1. noun: hereditary pattern in which a dominant gene on the X chromosome causes a characteristic to be manifested in the offspring

x-linked gene

1. noun: a gene located on an X chromosome

x-linked recessive inheritance

1. noun: hereditary pattern in which a recessive gene on the X chromosome results in the manifestation of characteristics in male offspring and a carrier state in female offspring

x-linked scid

1. noun: SCID in male children resulting from mutation of a gene that codes for a protein on the surface of T cells that allows them to develop a growth factor receptor

x-or circuit

1. noun: gate for exclusive OR; a circuit in a computer that fires only if only one of its inputs fire

x-radiation

1. noun: electromagnetic radiation of short wavelength produced when high-speed electrons strike a solid target
2. noun: obtaining images by the use of X rays

x-ray

1. noun: electromagnetic radiation of short wavelength produced when high-speed electrons strike a solid target
2. noun: a radiogram made by exposing photographic film to X rays; used in medical diagnosis

x-ray diffraction

1. noun: the scattering of X rays by the atoms of a crystal; the diffraction pattern shows structure of the crystal

x-ray film

1. noun: photographic film used to make X-ray pictures

x-ray machine

1. noun: an apparatus that provides a source of X rays

x-ray photograph

1. noun: a radiogram made by exposing photographic film to X rays; used in medical diagnosis

x-ray photography

1. noun: radiography that uses X-rays to produce a roentgenogram

x-ray picture

1. noun: a radiogram made by exposing photographic film to X rays; used in medical diagnosis

x-ray therapy

1. noun: the therapeutic use of X rays

x-ray tube

1. noun: a vacuum tube containing a metal target onto which a beam of electrons is directed at high energy for the generation of X rays

x-raying

1. noun: obtaining images by the use of X rays

x-scid

1. noun: SCID in male children resulting from mutation of a gene that codes for a protein on the surface of T cells that allows them to develop a growth factor receptor

xanax

1. noun: an antianxiety agent (trade name Xanax) of the benzodiazepine class

xanthate

1. noun: a salt or ester of xanthic acid

xanthelasma

1. noun: xanthoma of the eyelids; occurs chiefly in the elderly

xanthemia

1. noun: excess carotene in the blood stream; can cause the skin to turn a pale yellow or red color

xanthic acid

1. noun: any of a class of unstable organic acids containing sulphur

xanthine

1. noun: crystalline oxidation product of the metabolism of nucleoproteins; precursor of uric acid; found in many organs and in urine

xanthium

1. noun: coarse herbs having small heads of greenish flowers followed by burrs with hooked bristles

xanthoma

1. noun: a skin problem marked by the development (on the eyelids and neck and back) of irregular yellow nodules; sometimes attributable to disturbances of cholesterol metabolism

xanthoma disseminatum

1. noun: rare chronic xanthoma of adults in which orange or brownish papules develop on many surfaces of the body

xanthoma multiplex

1. noun: widespread xanthomas (especially on elbows and knees); often associated with a disorder of lipid metabolism

xanthomatosis

1. noun: widespread xanthomas (especially on elbows and knees); often associated with a disorder of lipid metabolism

xanthomonad

1. noun: bacteria producing yellow non-water-soluble pigments; some pathogenic for plants

xanthomonas

1. noun: a genus of bacteria similar to Pseudomonas but producing a yellow pigment that is not soluble in water

xanthophyceae

1. noun: yellow-green algae

xanthophyl

1. noun: yellow carotenoid pigments in plants and animal fats and egg yolks

xanthophyll

1. noun: yellow carotenoid pigments in plants and animal fats and egg yolks

xanthopsia

1. noun: visual defect in which objects appear to have a yellowish hue; sometimes occurs in cases of jaundice

xanthorrhoeaceae

1. noun: one of many subfamilies into which some classification systems subdivide the Liliaceae but not widely accepted

xanthorroea

1. noun: grass trees; sometimes placed in family Xanthorrhoeaceae

xanthosis

1. noun: an abnormal yellow discoloration of the skin

xanthosoma

1. noun: tropical American tuberous perennials

xanthosoma atrovirens

1. noun: tropical American aroid having edible tubers that are cooked and eaten like yams or potatoes

xanthosoma sagittifolium

1. noun: tropical American aroid having edible tubers that are cooked and eaten like yams or potatoes

xanthous

1. adjective: of the color intermediate between green and orange in the color spectrum; of something resembling the color of an egg yolk

xantusiidae

1. noun: night lizards

xavier

1. noun: Spanish missionary and Jesuit who establish missionaries in Japan and Ceylon and the East Indies (1506-1552)

xc

1. noun: the cardinal number that is the product of ten and nine
2. adjective: being ten more than eighty

xci

1. adjective: being one more than ninety

xcii

1. adjective: being two more than ninety

xciii

1. adjective: being three more than ninety

xciv

1. adjective: being four more than ninety

xcix

Spelling-list entry. A WordNet 3.1 definition is not available for this form.

xcl

1. adjective: being ten more than one hundred eighty

xcv

1. adjective: being five more than ninety

xcvi

1. adjective: being six more than ninety

xcvii

1. adjective: being seven more than ninety

xcviii

1. adjective: being eight more than ninety

xe

1. noun: a colorless odorless inert gaseous element occurring in the earth's atmosphere in trace amounts

xenarthra

1. noun: armadillos; American anteaters; sloths

xenicidae

1. noun: alternative names for the family comprising the New Zealand wrens

xenicus

1. noun: type genus for the Xenicidae

xenicus gilviventris

1. noun: short-tailed bird resembling a wren

xenogeneic

1. adjective: denoting or relating to cells or tissues from individuals belonging to different species

xenogenesis

1. noun: the alternation of two or more different forms in the life cycle of a plant or animal

xenograft

1. noun: tissue from an animal of one species used as a temporary graft (as in cases of severe burns) on an individual of another species

xenolith

1. noun: (geology) a piece of rock of different origin from the igneous rock in which it is embedded

xenon

1. noun: a colorless odorless inert gaseous element occurring in the earth's atmosphere in trace amounts

xenophanes

1. noun: Greek philosopher (560-478 BC)

xenophobe

Spelling-list entry. A WordNet 3.1 definition is not available for this form.

xenophobes

Spelling-list entry. A WordNet 3.1 definition is not available for this form.

xenophobia

1. noun: a fear of foreigners or strangers

xenophobic

1. adjective: suffering from xenophobia; having abnormal fear or hatred of the strange or foreign

xenophon

1. noun: Greek general and historian; student of Socrates (430-355 BC)

xenopodidae

1. noun: in some classifications the family of the genus Xenopus which is otherwise included in the family Pipidae

xenopus

1. noun: an African clawed frog; in some classifications made the type genus of a separate family Xenopodidae

xenopus laevis

1. noun: a tongueless frog native to Africa; established in the United States as result of release of laboratory and aquarium animals

xenorhyncus

1. noun: East Indian and Australian storks

xenorhyncus asiaticus

1. noun: large mostly white Australian stork

xenosauridae

1. noun: monotypic family of Mexican lizards

xenosaurus

1. noun: type and sole genus of Xenosauridae: slender-bodied Mexican lizards having the upper surface covered with tiny granules and tubercles

xenotime

1. noun: a brown-to-yellow mineral that is a phosphate of yttrium in crystalline form

xenotransplant

1. noun: a surgical procedure in which tissue or whole organs are transfered from one species to another species

xenotransplantation

1. noun: a surgical procedure in which tissue or whole organs are transfered from one species to another species

xeranthemum

1. noun: any plant of the genus Xeranthemum native to southern Europe having chaffy or silvery flower heads with purplish tubular flowers

xeranthemum annuum

1. noun: mostly widely cultivated species of everlasting flowers having usually purple flowers; southern Europe to Iran; naturalized elsewhere

xeric

1. adjective: being deficient in moisture; "deserts provide xeric environments"

xerobates

1. noun: possible new genus for desert and Texas tortoises based on recent research

xeroderma

1. noun: a mild form of ichthyosis characterized by abnormal dryness and roughness of the skin

xeroderma pigmentosum

1. noun: a rare genetic condition characterized by an eruption of exposed skin occurring in childhood and photosensitivity with severe sunburn; inherited as a recessive autosomal trait in which DNA repair processes are defective so they are more likely to chromosome breaks and cancers when exposed to ultraviolet light

xerodermia

1. noun: a mild form of ichthyosis characterized by abnormal dryness and roughness of the skin

xerographic

1. adjective: of or relating to xerography

xerographic copier

1. noun: a duplicator (trade mark Xerox) that copies graphic matter by the action of light on an electrically charged photoconductive insulating surface in which the latent image is developed with a resinous powder

xerographic printer

1. noun: a page printer that uses the xerographic process

xerography

1. noun: forming an image by the action of light on a specially coated charged plate; the latent image is developed with powders that adhere only to electrically charged areas; "edge enhancement is intrinsic in xerography"

xeroma

1. noun: abnormal dryness of the conjunctiva and cornea of the eyes; may be due to a systemic deficiency of vitamin A

xerophile

1. noun: plant adapted for life with a limited supply of water; compare hydrophyte and mesophyte

xerophilous plant

1. noun: plant adapted for life with a limited supply of water; compare hydrophyte and mesophyte

xerophthalmia

1. noun: abnormal dryness of the conjunctiva and cornea of the eyes; may be due to a systemic deficiency of vitamin A

xerophthalmus

1. noun: abnormal dryness of the conjunctiva and cornea of the eyes; may be due to a systemic deficiency of vitamin A

xerophyllum

1. noun: small genus of North American herbs having grasslike basal leaves: squaw grass; sometimes placed in family Melanthiaceae

xerophyllum tenax

1. noun: plant of western North America having woody rhizomes and tufts of stiff grasslike basal leaves and spikes of creamy white flowers

xerophyte

1. noun: plant adapted for life with a limited supply of water; compare hydrophyte and mesophyte

xerophytic

1. adjective: adapted to a xeric (or dry) environment; "cacti are xerophytic plants"; "xerophytic adaptations"

xerophytic plant

1. noun: plant adapted for life with a limited supply of water; compare hydrophyte and mesophyte

xeroradiography

1. noun: radiography using X-rays and xerographic (rather than roentgenographic) techniques

xerostomia

1. noun: abnormal dryness of the mouth resulting from decreased secretion of saliva

xerotes

1. noun: the condition of not containing or being covered by a liquid (especially water)

xerox

1. noun: a copy made by a xerographic copier
2. noun: a duplicator (trade mark Xerox) that copies graphic matter by the action of light on an electrically charged photoconductive insulating surface in which the latent image is developed with a resinous powder

xerox copy

1. noun: a copy made by a xerographic copier

xerox machine

1. noun: a duplicator (trade mark Xerox) that copies graphic matter by the action of light on an electrically charged photoconductive insulating surface in which the latent image is developed with a resinous powder

xeroxed

Spelling-list entry. A WordNet 3.1 definition is not available for this form.

xeroxes

Spelling-list entry. A WordNet 3.1 definition is not available for this form.

xeroxing

Spelling-list entry. A WordNet 3.1 definition is not available for this form.

xerxes i

1. noun: king of Persia who led a vast army against Greece and won the battle of Thermopylae but was eventually defeated (519-465 BC)

xerxes the great

1. noun: king of Persia who led a vast army against Greece and won the battle of Thermopylae but was eventually defeated (519-465 BC)

xestobium rufovillosum

1. noun: bores through wood making a ticking sound popularly thought to presage death

xhosa

1. noun: a member of the Negroid people of southern South Africa
2. noun: a community of Negroid people in southern South Africa

xi

1. noun: the cardinal number that is the sum of ten and one
2. noun: the 14th letter of the Greek alphabet

xian

1. noun: a city of central China; capital of ancient Chinese empire 221-206 BC