in figurative sense of "withdraw a charge," 1859, American English, from the notion of descending a ladder, etc. (such a literal sense is attested by 1849); from back (v.) + down (adv.).

"physically demanding" (of manual labor), 1849; see back (n.) + break (v.).

"a strong beat regularly falling on a normally unaccented beat of a bar," 1928, in jazz, from back (adj.) + beat (n.). Later also in popular music.

also pullback, 1660s, "act or action of pulling back," from the verbal phrase; see pull (v.) + back (adv.). From 1951 in the military sense of "orderly withdrawal of troops."

late 14c., "continue keeping of, keep possession of, keep attached to one's person;"  early 15c., "hold back, restrain" (a sense now obsolete); from Old French retenir "keep, retain; take into feudal service; hold back; remember" (12c.), from Latin retinere "hold back, keep back, detain, restrain," from re- "back" (see re-) + tenere "to hold" (from PIE root *ten- "to stretch").

The meaning "to engage to keep (another) attached to one's person, keep in service" is from mid-15c.; specifically of lawyers from 1540s. Meaning "keep in the mind, preserve knowledge or an idea of" is from c. 1500. Related: Retained; retaining.

mid-14c., "keep back or in store for future use;" late 14c., "keep as one's own," from Old French reserver "set aside, withhold" (12c.) and directly from Latin reservare "keep back, save up; retain, preserve," from re- "back" (see re-) + servare "to keep, save, preserve, protect" (from PIE root *ser- (1) "to protect"). Meaning "to book" is from 1935. Related: Reserved; reserving.

early 15c. (implied in deteined), "keep back or away, withhold," from Old French detenir "to hold off, keep back" (12c.), from Latin detinere "hold off, keep back," from de "from, away" (see de-) + tenere "to hold" (from PIE root *ten- "to stretch").

Legal sense of "to hold in custody" is from late 15c. (late 13c. in Anglo-French). Meaning "keep or restrain from proceeding" is from 1590s. Modern spelling is 17c., from influence of contain, retain, etc. Related: Detained; detaining.

late 15c., retarden, "make slow or slower; keep back, hinder, delay" (transitive), from French retarder "restrain, hold (someone) back, keep (someone from doing something); come to a stop" (13c.) and directly from Latin retardare "make slow, delay, keep back, hinder" (see retardation). Related: Retarded; retarding. The intransitive sense of "be delayed" is from 1640s. 

The noun retard is recorded from 1788 in the sense "retardation, delay;" from 1970 in the offensive meaning "retarded person," originally American English, with accent on first syllable. Other words used for "one who is mentally retarded" include retardate (1956, from Latin retardatus), and U.S. newspapers 1950s-60s often used retardee (1950).

late 15c., from Medieval Latin inhibitorius "inhibitory," from inhibit-, past participle stem of Latin inhibere "to hold in, keep back" (see inhibition).

late 14c., "avoid (something); refrain (oneself) from; keep free from sin or vice; live austerely, practice abstinence or asceticism; be sexually continent," from Old French abstiner, abstenir (14c.), earlier astenir (13c.) "hold (oneself) back, refrain voluntarily, abstain (from what satisfies the passions), practice abstinence," from Latin abstinere "withhold, keep back, keep off," from assimilated form of ab "off, away from" (see ab-) + tenere "to hold" (from PIE root *ten- "to stretch"). Specifically of liquor from late 14c. Meaning "refrain from voting" is from 1796. Related: Abstained; abstaining.