Old English delfan "to dig" (class III strong verb; past tense dealf, past participle dolfen), common West Germanic verb (cognates: Old Saxon delban, Dutch delven, Middle High German telben "to dig"), from PIE root *dhelbh- (cognates: Lithuanian delba "crowbar," Russian dolbit', Czech dlabati, Polish dłubać "to chisel;" Russian dolotó, Czech dlato, Polish dłuto "chisel"). Weak inflections emerged 14c.-16c. Related: Delved; delving.