seriously
要点真剣に、重大に
意味
- 真剣に,まじめに,本気で
- 重大に,ひどく
例文
Don't make fun of me when I'm talking seriously.
人が真剣に話してるのに茶化さないでよ。
I'm seriously too busy, so I can't come tonight.
マジ忙しくて、今夜は来れないよ。
It's seriously heavy, so there's no way I could.
マジで重いから絶対ムリ。
語源
英語の原文（Wiktionary）
From Middle English seriously, sereously, ceryously, seryowslech (“earnestly”), equivalent to serious + -ly.