procumbent (adj.)youdaoicibaDictYouDict[procumbent 词源字典]
"leaning forward," 1660s, from Latin procumbentem (nominative procumbens), present participle of procumbere "to fall forward, fall prostrate," from pro "forward" (see pro-) + -cumbere "to lie down" (see succumb). Related: Procumbently.[procumbent etymology, procumbent origin, 英语词源]