Basque boa “a kind of small fish”
Azkue lists the following:
(B-Lekeitio) boa “a kind of small fish”
(B-Lekeitio, G-Donostia) boga “a white fish that is found among rocks”
boa is attested only in Lekeitio, which is a fishing port, so it is likely that the small fish in question is a sea fish. boga is attested in only two places, one of which is Lekeitio, so it is likely that the two words, boa and boga, are connected. Possibly, the final /a/ of both words is a late addition and the medial /g/ of boga is connective, replacing, perhaps, a medial /h/ that was added some time in the first millennium AD.
Azkue does not specify which small fish is meant by boa, and which fish that lives among the rocks is meant by boga.
Spanish bogar, Old French voguer, etc, “to row, sail”, a Western Romance word of unknown origin, is present in Basque, but it is unlikely to have become an ichthyonym (word for a fish) because the meanings are too remote from each other.
Is this word present in Iberian? Possibly.
Iberian bo is an anthroponymic compound element. It is present mostly in tripartite anthroponyms, sometimes initially and sometimes medially. It performs a similar role to Iberian ge “smoke”. Consider the following:
East Iberian Script
Bobaidinba (Los Villares)
Guduboike (Orleyl)
Karespobixir (Liria)
Ionian Script
Boistingis (Alcoy)
The kind of fish meant by Iberian bo, if indeed it is an ichthyonym, is unknown.
Does Basque boa, Iberian bo have cognates in other Vasconic languages further afield? Quite probably. There is Latin boa, “a kind of snake”, mentioned by Pliny. The word has subsequently been appropriated to mean a large constricting snake found mainly in Latin America, but Pliny did not specify what kind of snake it was. It may not have been a large python like snake.
Words for “fish” can also be words for “snake”. For instance, Latin lacerta can mean both “lizard” and “sea fish”.
Does Basque boa, Iberian bo have cognates in other non-Vasconic Dene-Caucasian languages? Possibly. Consider the following:
Yeniseian (Ket) bɔŋtuɣ “herring”
There are a few preliminary things to say about Ket bɔŋtuɣ. Firstly, the word is a compound. The relevant part is bɔŋ-. Secondly, Starostin’s translation cannot be right. The herring is a sea fish that would not have been known to speakers of any Yeniseian language. Thirdly, if this word is indeed cognate with Basque boa, Iberian bo, it would suggest a prehistoric final /n/ variant that is either original or runs in parallel.
Iberian bo and Latin boa suggest no final /n/ at the Proto-Vasconic stage (Iberian and Italian Vasconic appear to agree on this). A final /n/ would likely have caused the initial /b/ to shift to /m/. However, there is some reason to hold that a final /n/ variant does exist in parallel and that it did shift the initial /b/ to /m/. Consider the following, both listed by Azkue:
(B-Lekeitio) moma, (B) momar “small-spotted cat shark” (where -ar is the masculine suffix)
It is possible that a cognate was present in German Vasconic that gave rise to German Münne “a kind of fish” and English minnow, a small freshwater fish.