late 14c., of substances, "closely and firmly united," from Latin compactus "concentrated," past participle of compingere "to fasten together, construct," from com "with, together" (see com-) + pangere "to fix, fasten" (from PIE root *pag- "to fasten"). Related: Compactly; compactness. Compact car is 1960. Compact disc is from 1979.
"to pack or press closely together," early 15c., from Latin compactus, past participle of compingere "to fasten together" (see compact (adj.)). Related: Compacted; compacting.
"small make-up case," 1919, from compact (adj.), based on its containing compacted face powder.
"to make a compact, enter into an agreement," 1530s, from compact (n.1) or else from Old French compacter. Related: Compacted; compacting.