deriv LSK ETT STT aSTA ALPH OLDHOMEPAGE NEWHOMEPAGE
The /taddhita affix /in means 'having' by !! —
bala- बलॱ + /in → balin- बलिन्
pakSin- पक्षिन्
yogin- योगिन्
See also /ini and /Nini.
The feminine of all these takes /GIp by RnnebhyoGIp.