Meaning of “green” - Learner’s Dictionary

green

adjective uk us /ɡriːn/
COLOUR

A1 being the same colour as grass:

The traffic lights turned green.
GRASS

B1 covered with grass or other plants:

green spaces
NOT EXPERIENCED informal

having little experience or understanding:

I was very green when I joined the company.

(Definition of “green adjective” from the Cambridge Learner’s Dictionary © Cambridge University Press)