プログレッシブ和英中辞典(第4版)の解説
あね【姉】
one's older [elder] sister；《口》 one's big sister（▼特に子供が言う場合）
一番上の姉
one's oldest [eldest] sister（▼ 《米》 ではolder，oldestを用いる傾向が強い）
腹違いの姉
one's [an] older half sister
義理の姉
one's sister-in-law／one's older brother's wife
姉婿
one's older [elder] sister's husband