ハイhai

1. na-adjective, nounhigh (spirits); euphoric; intoxicated
   何度なんども「やめましょうよ」と言いったのに、何なん杯ばいもワインを飲み干のみほし――ご覧らんの通とおり、酔っ払よっぱらってハイになってしまったのである。↗

   I kept saying "Let's stop" but she drained cup after cup of wine ― and now, as you can see, she's completely drunk.
2. prenominal modifierhigh

• RelatedのりのりCasualColloquial: being in high spirits and really into something, as in 「ノリノリで歌う」. 「ハイ」 goes further, also covering high or high-grade things, not just mood.
• AntonymローNeutralLoanword meaning low or low gear, as in 「ローテンション」「ローギア」; the opposite of 「ハイ」 on the high–low scale.

Use 「ハイ」 for high spirits or for high and high-grade things, as in 「ハイテンション」「ハイレベル」; for being in high spirits and into something, say 「ノリノリ」; the opposite is 「ロー」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 高たかいさま。
2. 気分きぶんが高揚こうようしたさま。