Whelk, the name for marine gasteropod mollusks belonging especially to the family of Buccinidæ. The common whelk of the northern Atlantic is eaten in England. These animals look somewhat like very large snails. The shell is pointed, but has only a few whorls. The animal has a broad body, with tentacles projecting from the head. It can be entirely retracted within its shell. It burrows in the sand, and feeds on clams and other bivalve mollusks. Some whelks are used for bait.