Dictionary.net

grant credentials to; "recognize a new educational institution"l "recognize an academic degree"

express obligation, thanks, or gratitude for; "We must acknowledge the kindness she showed towards us"

detect with the senses; "The fleeing convicts were picked out of the darkness by the watchful prison guards"; "I can't make out the faces in this photograph"

express greetings upon meeting someone

express obligation, thanks, or gratitude for; "We must acknowledge the kindness she showed towards us"

detect with the senses; "The fleeing convicts were picked out of the darkness by the watchful prison guards"; "I can't make out the faces in this photograph"

express greetings upon meeting someone

accept (someone) to be what is claimed or accept his power and authority; "The Crown Prince was acknowledged as the true heir to the throne"; "We do not recognize your gods"

grant credentials to; "The Regents officially recognized the new educational institution"; "recognize an academic degree"

To know again; recollect; acknowledge; perceive.