第だい一いち四し半はん期きだいいちしはんきMeanings1nounfirst quarter (of the year)Business term for January–March (Q1) in financial or fiscal contexts.当とう社しゃの第だい一いち四し半はん期きの売うり上あげは前ぜん年ねん比ひで増ぞう加