The word 'walrus' entered English in the late 17th century from Dutch 'walrus'. The Dutch term is likely a folk-etymological alteration of an earlier Scandinavian word, such as Old Norse 'hrossvalr', which literally meant 'horse-whale'. This compound described the creature's size and marine habitat. The modern form 'walrus' may have been influenced by Dutch words like 'wal' (shore) and 'ros' (horse), reinforcing the idea of a large, coastal animal. Its journey reflects the European encounter with Arctic fauna and the subsequent reshaping of foreign words to fit familiar linguistic patterns.

This word is a simplex loanword. Its components within the English spelling ('wal' and 'rus') do not correspond to independent, meaningful morphemes in English.