means A massive marine mammal of the order Cetacea that breathes air, nurses its young, and lives entirely in the sea.

from From Old English 'hwæl,' the word for these sea-giants, with relatives across the Germanic family — Old Norse 'hvalr,' Old High German 'wal.' Linguists trace it back to a Proto-Germanic root, and some link it further to a Proto-Indo-European source that may also be a cousin of Latin 'squalus,' a kind of large sea-fish — though that older connection is debated rather than certain. The 'wh-' spelling preserves an old 'hw-' sound that English mouths have long since softened.