Quick answer
Keiko is a girl name.
Meaning and history
From Japanese 慶 ( kei ) meaning "celebration", 敬 ( kei ) meaning "respect", 啓 ( kei ) meaning "open, begin" or 恵 ( kei ) meaning "favour, benefit" combined with 子 ( ko ) meaning "child". Other kanji combinations are possible.
Notes and context
Usage: japanese | Japanese Hiragana: けいこ; Japanese Katakana: ケイコ