means A large, long-necked waterbird, usually white, famous for its graceful glide and notoriously aggressive defense of its territory.

from From Old English 'swan,' shared across the Germanic languages (Dutch 'zwaan,' German 'Schwan'). The deeper root is often linked to a Proto-Indo-European base meaning 'to sound' or 'to sing' — a cousin, perhaps, of Latin 'sonus' — which would tie the bird's name to the old legend of the dying swan's song. The verb sense, 'to swan about,' came much later and quite separately, an English flourish riffing on the bird's languid, self-satisfied movement.