adj. 1 a lying face downwards (cf. SUPINE). b lying flat; prostrate. c having the front part downwards, esp. the palm of the hand. 2 (usu. foll. by to, or to + infin.) disposed or liable, esp. to a bad action, condition, etc. (is prone to bite his nails). 3 (usu. in comb.) more than usually likely to suffer (accident-prone). 4 archaic with a downward slope or direction. pronely adv. proneness n.
[ ME f. L pronus f. pro forwards ]