The kinship sense (older woman / mother / sister-in-law term) is dialectal — mostly Wu and Min areas — and feels old-fashioned in standard Mandarin. Use 阿姨 (āyí) for everyday 'auntie'.
culture
Far more common in modern usage: 阿姆 is the standard Chinese transliteration of American rapper Eminem (full name 埃米纳姆 Āimǐnàmǔ, but he's universally known as 阿姆 in Chinese hip-hop coverage).
