Etymologically, does anyone know if the Irish term for the basking shark – liamhán – can be broken down to some root that gives a clue as to the literal meaning of the name liamhán? (i.e., like how swordfish can be broken down to sword + fish, or the bird “swift” refers to its speed, or “porpoise” comes from the Latin porcus “pig” + piscis “fish”)
I have no idea, but can only speculate. The “-án” suffix is an exceedingly common noun suffix which doesn’t have an exact meaning, per se, it mostly just means “thing”. Liamh looks and sounds a bit like leamh, which makes a little sense if you think of them as slow harmless creatures. I also see that another form in the dictionary is “liab(h)án”, but that doesn’t really offer any clues to me. So I guess have that guess, which might not be worth anything. It’s probably from an older word, if anything.
I don’t know if it’s fair to say that -án is always diminutive. In many cases it does function that way, but there are just as many where it serves a much more general function as well. Safe to say that I don’t think a basking shark is a little version of another thing.
Is it possible that liamhán is a noun or adjective form of “líomh(adh), to grind, sharpen; file, smooth, polish” — basking shark skin is very rough, so maybe the animal was named for its sandpaper texture?