Noun
one shot; one charge; one explosion
トムは頭にきつい一発を受けた。Tom received a heavy blow on the head. one blow; one punch
home run
Baseball
Noun, Adverb (fukushi)
one try; one attempt
Noun
win on the first go-around after calling rīchi
ippatsu (comp. karuta); taking a card which is read immediately after sending it
Card gamesAbbreviationsee 送り一発
Also written 1発【いっぱつ】