From lielains (“having growth on side”) + -ums (with lielains from liels (“big, large”) + -ains).
lielainums m (1st declension)
| singular (vienskaitlis) | plural (daudzskaitlis) | |
|---|---|---|
| nominative (nominatīvs) | lielainums | lielainumi |
| accusative (akuzatīvs) | lielainumu | lielainumus |
| genitive (ģenitīvs) | lielainuma | lielainumu |
| dative (datīvs) | lielainumam | lielainumiem |
| instrumental (instrumentālis) | lielainumu | lielainumiem |
| locative (lokatīvs) | lielainumā | lielainumos |
| vocative (vokatīvs) | lielainum | lielainumi |