caveat (n.) Look up caveat at Dictionary.com
1540s, from Latin, literally "let him beware," 3rd person singular present subjunctive of cavere "to beware, take heed, watch, guard against," from PIE root *skeue- "to pay attention, perceive" (cognates: Sanskrit kavih "wise, sage, seer, poet;" Lithuanian kavoti "tend, safeguard;" Armenian cucanem "I show;" Latin cautio "wariness;" Greek koein "to mark, perceive, hear," kydos "glory, fame," literally "that which is heard of;" Old Church Slavonic chujo "to feel, perceive, hear," cudo "wonder," literally "that which is heard of;" Czech (z)koumati "to perceive, be aware of;" Serbian chuvati "watch, heed;" Old English sceawian "to look at" (source of show (v.)); Middle Dutch schoon "beautiful, bright," properly "showy;" Gothic hausjan "hear").