—adj. 1. having relatively great extent from one surface or side to the opposite; not thin: a thick slice. 2. measured, as specified, between opposite surfaces, from top to bottom, or in a direction perpendicular to that of the length and breadth; (of a solid having three general dimensions) measured across its smallest dimension: a board one inch thick. 3. composed of or containing objects, particles, etc., close together; dense: a thick fog; a thick forest. 4. filled, covered, or abounding (usually fol. by with): tables thick with dust. 5. husky or hoarse; not distinctly articulated: The patient's speech is still quite thick. 6. markedly so (as specified): a thick German accent. 7. deep or profound: thick darkness. 8. (of a liquid) heavy or viscous: a thick syrup. 9. Informal.close in friendship; intimate.
10. mentally slow; stupid; dull.
11. disagreeably excessive or exaggerated: They thought it a bit thick when he called himself a genius.
—adv. 1. in a thick manner.
2. close together; closely packed: The roses grew thick along the path. 3. in a manner to produce something thick: Slice the cheese thick. 4. lay it on thick,Informal.to praise excessively; flatter: He's laying it on thick because he wants you to do him a favor.
—n. 1. the thickest, densest, or most crowded part: in the thick of the fight. 2. through thick and thin, under favorable and unfavorable conditions; steadfastly: We have been friends for 20 years, through thick and thin.