Filed under: Words of the Months
Etymology: Probably from Anglo-French merilun, contracted from Old French esmerillon, ‘small hawk’.
Definition: Falco columbarius, a species of small falcon.
The merlin is native to much of the Northern hemisphere. Its summer range includes much of Canada, Russia, Scandinavia, and parts of the British Isles. Its winter range includes southern Japan, Mexico & the U.S., much of Europe, the Caribbean, other parts of the British Isles, and southeast China.
The wizard Merlin, surprisingly, is not named for the bird; Merlinus is a Latinisation of the Welsh Myrddin(pronounced approximately merthin [with th voiced]).
There is a claim, which I cannot verify at this time, that Geoffrey of Monmouth chose Merlinus over Merdinus (apparently a more conventional Latin rendering) to avoid association with the scatological merde.
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