noun
the 'a' column of the Japanese syllabary table (a, i, u, e, o)
Refers to the row of kana starting with the vowel 'a': あいうえお (hiragana) or アイウエオ (katakana). Used in discussions of Japanese phonology, kana order, and dictionary arrangement.
五十音図のあ行は「あいうえお」です。
The 'a' row of the gojūon chart is 'a, i, u, e, o'.
辞書では、あ行の次にか行が来ます。
In the dictionary, the 'ka' row comes after the 'a' row.
Compound of あ (a, the first kana) + 行 (ぎょう, row/line), referring to the row of the kana table that begins with あ.