early 14c., probably from a parallel form of Old English -hwielfan (West Saxon), -hwelfan (Mercian), in ahwelfan "cover over;" probably altered by association with Old English helmian "to cover," from Proto-Germanic *hwalbjan, from PIE *kwelp- "to arch" (see gulf (n.)).
双语例句
1. Counterfeit parts , in fact, could one day over whelm genuine parts.
