An aquaholic is a joking name for someone who drinks a great deal of water every day — bottle after bottle, as if they cannot stop. It is not a doctor’s word and not a real illness. English built it the same way as workaholic: take the -holic ending that people hear in alcoholic (someone who cannot stop drinking alcohol) and stick it onto aqua-, a piece that means “water”. The tone is playful, a little headline, a little gym-and-wellness. You might say it about a friend who always has a huge bottle on the desk, or about yourself, with a smile. Though actually, some people stretch it toward anyone who loves being in water, but the core joke is about drinking water, not about swimming. You would not put it in a serious school essay unless you were clearly being funny.

戲稱「超愛喝水、一天喝很多水的人」。不是病名。台灣日常多半直接說「他超愛喝水」，沒有真正固定的詞。