Origin of merlinMiddle English merlion from Old French esmerillon, diminutive of esmeril, merlin from Old High German smirl, merlin
Origin of MerlinMedieval Latin Merlinus from Welsh Myrrdin from Brythonic an unverified form Mori-dünon from an unverified form mori, sea + Proto-Celt an unverified form dunom, hill, fortified hill, fort, hence, literally , sea-hill or sea-fortress
Origin of merlinMiddle English from Anglo-Norman merilun from Old French esmerillon diminutive of esmeril of Germanic origin
From Middle English merlone, merlion, marlyon, merlyon, merlinge, from Old French emerillon, esmerillon, from Old Frankish *smiril (“falcon, hawk"), from Proto-Germanic *smirilaz (“falcon, merlin"). Cognate with Old High German smirl (“falcon"), Old Norse smyrill (“falcon").
From "Moesin-Ezrin-Radixin-Like Protein"
Latin Merlinus, itself from the Old Welsh Myrddin.