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rock 1 (rŏk)
1. Relatively hard, naturally formed mineral or petrified matter; stone.
a. A relatively small piece or fragment of such material.
b. A relatively large body of such material, as a cliff or peak.
3. A naturally formed aggregate of mineral matter constituting a significant part of the earth's crust.
4. One that is similar to or suggestive of a mass of stone in stability, firmness, or dependability: The family has been his rock during this difficult time.
5. rocks Slang Money.
6. Slang A large gem, especially a diamond.
7. Slang Crack cocaine.
a. A varicolored stick candy.
b. Rock candy.
between a rock and a hard place
Confronted with equally unpleasant alternatives and few or no opportunities to evade or circumvent them.
on the rocks
1. In a state of difficulty, destruction, or ruin: Their marriage is on the rocks.
2. Without money; bankrupt: Our accountant says the business is on the rocks.
3. Served over ice cubes: Scotch on the rocks.

[Middle English, from Old North French roque, from Vulgar Latin *rocca, of unknown origin .]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
rock 2 (rŏk)
v. rocked, rock·ing, rocks
1. To move back and forth or from side to side, especially gently or rhythmically.
2. To sway violently, as from a blow or shock. See Synonyms at swing.
3. To be washed and panned in a cradle or in a rocker. Used of ores.
4. Music To play or dance to rock music.
5. Slang To be excellent or outstanding. Used in exclamations of approval.
1. To move (a child, for example) back and forth or from side to side, especially in order to soothe or lull to sleep.
2. To cause to shake or sway violently. See Synonyms at agitate.
a. To disturb the mental or emotional equilibrium of; upset: News of the scandal rocked the town.
b. To excite or cause strong feeling in, as by playing rock music.
4. To wash or pan (ore) in a cradle or rocker.
5. In mezzotint engraving, to roughen (a metal plate) with a rocker or roulette.
6. Slang To exhibit, display, or use with flair: The actor rocked a pair of diamond-studded sunglasses at the movie premiere.
a. A rocking motion.
b. The act of rocking.
2. Music A form of popular music characterized by electronically amplified instrumentation, a heavily accented beat, and relatively simple phrase structure. Originating in the United States in the 1950s, rock incorporates a variety of musical styles, especially rhythm and blues, country music, and gospel. Also called rock-and-roll, rock 'n' roll.
rock the boat
To disturb the balance or routine of a situation: He has an easygoing managerial style and won't rock the boat unless absolutely necessary.

[Middle English rokken, from Old English roccian.]

rocking·ly adv.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.