Ailm

Ailm is the Irish name of the sixteenth letter of the Ogham alphabet, ᚐ. Its phonetic value is [a]. The original meaning of the name cannot be established with certainty.[1] The Bríatharogam kennings all refer to the sound [a] and not to the meaning of the letter name, either as the sound of a "groan", or to the Irish vocative particle, á. Thurneysen suggests that Ailm, Beithe was influenced by Alpha, Beta. However, beithe is an Irish word, and there is no reason to consider ailm a sole, loaned letter name among the original feda; Thurneysen did not suggest this letter name involved such a borrowing.[2] The word is attested once outside of the Ogham grammatical texts, in the poem "King Henry and the Hermit",

caine ailmi ardom-peitet

which translates to

Beautiful are the pines which make music for me.[3]

This single reference is the reason ailm is sometimes associated with pines. However, the poem likely post-dates origins of the medieval tradition of arboreal glosses of the ogham letters, so is more probably influenced by this tradition than an independent source for the meaning of ailm.[4]