| xerostomia | n. | dry mouth | ||
| yadder | v. | to talk meaninglessly, to speak of trivialities; to brace with a stake | ||
| yarak | n. | (of a hawk) in prime condition for hunting | ||
| yashmak | n. | veil worn by Muslim women when in public | ||
| yataghan | n. | Ottoman doubly curved saber | ||
| yeet | v. | to throw something with great force; general affirmative exclamation | slang | |
| yen shee | n. | opium pipe bowl ashes and residue | ||
| yester | adj. | of or relating to yesterday | archaic | |
| yett | n. | gate | Scots | |
| yobbo | n. | yob, young lout | British | |
| yoctosecond | n. | 10−24 seconds, one septillion of a second, one trillionth of a trillionth of a second | ||
| yoicks | int. | fox hunting cry used to urge on the hounds; exclamation of exultation or excitement | ||
| yonks | n. | a very long time | British | |
| younker | n. | youngster | ||
| zareba | n. | protective enclosure, as of thorn bushes or stakes | ||
| zendado | n. | sendal, light cloth of silk; veil made of such cloth | ||
| Zepp | n. | sausage | slang | |
| zetetic | adj. | proceding by investigation (often used in contradistinction to pejorative view of the term “skeptic”) | ||
| zeugma | n. | use of a word to modify two other words either in two different senses or in an inappropriate (sometimes for humorous effect) fashion | rhetoric | |
| zoeal | adj. | of or related to one of the larval stages of certain crustaceans such as crabs | ||
| zone | n. | girdle, belt, cestus | ||
| zonulet | n. | little zone | archaic | |
| zugzwang | n. | a position in chess in which every move leads to a worse situation |
