mid-14c., "a consideration; a judgment," from Old French regard, from regarder "take notice of," from re-, intensive prefix + garder "look, heed" (see guard (n.)). Meanings "a look, appearance; respect, esteem, favor, kindly feeling which springs from a consideration of estimable qualities" all recorded late 14c. Phrase in regard to is from mid-15c. (Chaucer uses at regard of).
mid-14c., "consider" (that something is so), from Middle French regarder "to look at," from regard (see regard (n.)). Meaning "look upon, observe" is from 1520s, as is that of "observe a certain respect toward." Related: Regarded; regarding.