I'm learning Gàidlig (tha beagan Gàidhlig agam fhathast) and I've tried to find out what Neachdainn means. "Neach" means person and this is definitely fitting for your wee pal, but I couldn't find an explanation for -dainn.
It was originally a Pictish name, Neachdainn is the Gàidhlig spelling. In English it is Nechtan. There were several Pictish kings with the name, and Neachdainn was born in the same area as one of his regal forebears.
I believe the meaning of the name is lost in the mists of time.
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