I don't think so, franc. In verse 3 there's "cailín stuama" ("stuama": adjective = 'sensible, prudent; skilful, steady' according to my foc poc).

I've never seen it before , but my semi-educated guess is that "stuabhean" ("stua": noun = 'arch; arc', 'stua ceatha' = 'rainbow') follows the pattern "spéirbhean" and would be similar in meaning.

Grma as na liricí a chur suas.

It was because I saw that there's a broad vowel followed by a slender - I thought they might have squeezed two words together or that perhaps there was a spelling mistake there.

I'm not sure how yon skinny/fat vowel rules apply in compound words - the likes of long-established 'ansin/anseo' apart obviously. Best wait for a grammar heavyweight to weigh in.

I've seen the same word in the male context. In the song Éist do bhéal on the CD Éist, the female narrator in the song refers to herself as being seen in a dream walking on the shore "lem' stuafhear rua", which the liner notes translate as "with a fine foxy man", but which is a bit closer to "with my red-haired stud" (not the four-footed kind!).

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I'm not a native (or entirely fluent) speaker, so be sure to wait for confirmations/corrections, especially for tattoos.