adj. thick·er, thick·est
a. Relatively great in extent from one surface to the opposite, usually in the smallest solid dimension; not thin: a thick board.
b. Measuring a specified number of units in this dimension: two inches thick.
2. Heavy in form, build, or stature; thickset: a thick neck.
3. Having component parts in a close, crowded state or arrangement; dense: a thick forest.
4. Having or suggesting a heavy or viscous consistency: thick tomato sauce.
5. Having a great number; abounding: a room thick with flies.
6. Impenetrable by the eyes: a thick fog.
a. Hard to hear or understand, as from being husky or slurred: thick speech.
b. Very noticeable; pronounced: has a thick accent.
8. Informal Lacking mental agility; stupid.
9. Informal Very friendly; intimate: thick friends.
10. Informal Going beyond what is tolerable; excessive.
1. In a thick manner; deeply or heavily: Seashells lay thick on the beach.
2. In a close, compact state or arrangement; densely: Dozens of braids hung thick from the back of her head.
3. So as to be thick; thickly: Slice the bread thick for the best French toast.
1. The thickest part.
2. The most active or intense part: in the thick of the fighting.
thick and thin
Good and bad times: They remained friends through thick and thin.
[Middle English thicke, from Old English thicce; see tegu- in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.