The noun birth has 4 senses (first 3 from tagged texts)
1. (6) birth -- (the time when something begins (especially life); "they divorced after the birth of the child"; "his election signaled the birth of a new age")
2. (2) birth, nativity, nascency, nascence -- (the event of being born; "they celebrated the birth of their first child")
3. (1) parturition, birth, giving birth, birthing -- (the process of giving birth)
4. parentage, birth -- (the kinship relation of an offspring to the parents)
Overview of verb birth
The verb birth has 1 sense (no senses from tagged texts)
1. give birth, deliver, bear, birth, have -- (cause to be born; "My wife had twins yesterday!")