An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

1) Coming into being or notice.
2) Philo.: (of a property) arising as an effect of complex causes and not analyzable simply as the sum of their effects.
3) Ecology: Of or denoting a plant which is taller than the surrounding vegetation, especially a tall tree in a forest (OxfordDictionaries.com).

→ emerge; → -ent.

Optics: The → light ray leaving a → medium, in contrast to the → incident ray. If the medium has parallel sides, → angle of incidence and → angle of emergence

→ emergent; → ray.