1 identify, detect, place, recall, remember, recollect, know (again):
I recognized him from seeing his picture in the newspaper.
2 acknowledge, perceive, understand, realize, see, admit, accept, own, concede, allow, grant, appreciate, respect, be aware of:
He refuses to recognize that he is responsible for his own actions.
3 approve, sanction, endorse, accept, validate, ratify:
A totalitarian government refuses to recognize the rights of the individual
4 honour, give recognition to, salute, show gratitude or appreciation, reward, distinguish, pay respect, do homage:
The society recognizes Dr Jackson for his many contributions to science.