catamaran

From Tamil கட்டுமரம் (kaṭṭumaram), a compound of கட்டு (kaṭṭu, "to tie") and மரம் (maram, "tree, wood").

The word simply carried its literal meaning — tied logs — from Tamil into English as the name for this style of multi-hulled boat.

It shares its second half, மரம் (maram, "wood"), with the very material the original vessels were made from, though no English cognate is given in the facts.