noun
Counter-like noun for a single document, letter, or similar item. Often used with 書類, 手紙, はがき, etc.
申込書を一通提出してください。
Please submit one copy of the application form.
昨日、友人から手紙が一通届いた。
I received one letter from a friend yesterday.
noun
Abbreviation of 一方通行. Used in traffic contexts; may appear on signs or in casual speech.
See also: 一方通行
この道は一通だから、入れないよ。
This road is one-way, so you can't enter.
noun
pure straight; 1-9 straight
Mahjong term: a winning hand with tiles 1 through 9 of the same suit. Abbreviation of 一気通貫. Sometimes written in katakana as イッツー.
See also: 一気通貫 (いっきつうかん)
彼は一通を上がって逆転した。
He won with a pure straight and turned the game around.
Full term for one-way traffic; 一通 is its abbreviation.
Full mahjong term for the pure straight hand; 一通 is its abbreviation.
Compound of 一 (one) and 通 (counter for documents/letters). The traffic and mahjong senses are abbreviations of longer terms.