English translations for the name あこ (Ako) seem tough to find, and are unsourced, so I don't know what to believe. Some say cute, others child, even wife!
あこ as a Japanese girl name, can be displayed in a lot of different Kanji characters, depending on what the parents choose (They're all pronounced the same as AKO).
吾子ーー＞(These two characters meaning "my child")
和心----> (could mean "harmonious heart")
For those above beginning with Kanji "亜", which means someone or something comes in the 2nd place, or sometimes it could be a transliteration of "Asia" (derived from the first vowel of the English world "Asia"), I'd suggest you look up the other Kanji following 亜 individually.
The online dictionary, URL as below: http://nihongo.monash.edu/cgi-bin/wwwjdic?1C
The most used word that sounds 'あこ' is '吾子,' which is a very oldish expression meaning "my child" that appears pretty often in old anthologies like 万葉集.
When you input 'ako' in MS Word, you get '亜子,' '阿子,' '阿古,' and '阿児' as a conversion. '亜子' is a pretty familiar name of women. But I don't know what the last two words mean, and if they make sense.
アコ in katakana is often used as a nick name for 敦子, 厚子, 亜津子, 亜紀子, 明子, アキ子 and etc.
和田アキ子, one of the most popular and long-life female pop singer is loved by the nick name of アッコ.