benâ -> bean
bnâs -> mná

-than plural suffix.

Labhrás, would you happen to know if this is a purely Scottish Gaelic suffix or did the form “mnathan” at some point also exist in Irish Gaelic? I thought the plural form was “mná” already in Classical Old Irish…

I don’t know if other plural forms of “bean” beside “mná” (/mna:/, /mra:/) exist or existed in Irish.
I guess the Irish equivalent for -an is -anna , The th in Scottish Gaelic -than is probably silent and due to the hiatus between mna- and -an .
-an is a frequent plural suffix in Gàidhlig, much more so than Irish -anna, so I’m not surprised about “mnathan”.

Ah, that’s interesting! So technically, “mnathan” has two plular markers – the special plural stem “mna” plus the plural ending “-an”. 🙂