Definition of me pronoun from the Oxford Advanced Learner's Dictionary

BrE BrE//mi//
; NAmE NAmE//mi//
; BrE strong form BrE//miː//
; NAmE strong form NAmE//miː//
the form of I that is used when the speaker or writer is the object of a verb or preposition, or after the verb be Don't hit me. Excuse me! Give it to me. You're taller than me. Hello, it's me. ‘Who's there?’ ‘Only me.’ The use of me in the last three examples is correct in modern standard English. I in these sentences would be considered much too formal for almost all contexts, especially in British English.
Word Originpronoun Old English , accusative and dative of I (pronoun), of Germanic origin; related to Dutch mij, German mir (dative), from an Indo-European root shared by Latin me, Greek (e)me, and Sanskrit .
See the Oxford Advanced American Dictionary entry: me