Quenya 

nosta

birth, birthday

nosta noun "birth, birthday" (LT1:272; maybe not a valid word in Tolkiens later Quenya because the meaning of the corresponding verb was changed from "give birth" to "beget")

* nónië

noun. birth
Quenya Group: Neologism. Published by

Sindarin 

* onnad

noun. birth
Sindarin Group: Neologism. Published by

Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!

Gnomish

nosteg

adjective. birth
Gnomish [GL/61.3304] Group: Eldamo. Published by