own（adj.）
"properly or exclusively belonging to one's self or itself," Middle English ouen, from Old English agen, literally "possessed by," from Proto-Germanic *aiganaz "possessed, owned" (source also of Old Saxon egan,, Old Frisian egin,, Old Norse eiginn,, Dutch eigen,, German eigen "own"), from past participle of PIE root *aik- "be master of, possess," source of Old English agan "to have" (see owe). Emphatic use after a possessive noun or pronoun is from late Old English. To hold one's own "maintain one's position" is by 1520s.