Usage: 3 forms in 15 verses
Form Translated As     In Verse(s)
πρωτογεννημάτων first produce LXX.Exod.23.19LXX.Lev.2.14LXX.Lev.23.19LXX.Lev.23.20LXX.2Kgs.4.42
of first produce LXX.Lev.2.14LXX.Lev.23.17
of the first produce LXX.Exod.23.16
πρωτογεννήματα first produce LXX.Exod.34.26LXX.Num.18.13LXX.Neh.10.35LXX.Neh.10.35LXX.Ezek.48.14
your first produce LXX.Ezek.44.30
προτογεννήμασι first produce LXX.Neh.13.31

Liddell-Scott-Jones

πρωτογέννημα (prōtogennēma) first produce G:N-N

πρωτογέννημα-γένημα, ατος, τό,

firstfruits, [LXX+1st c.AD+]

LSJ Scripture Refs: LXX.Exod.34.26