Light-headed means faint and floaty in the head, close to passing out. The room is not quite steady.
It is caused by standing up too fast, low blood sugar, heat, dehydration or fear, and it is the warning sign before fainting rather than the fainting itself. Sitting down at once is the correct response. The word is written with a hyphen. Dizzy overlaps and strictly means the room appears to spin, which is a different sensation doctors distinguish carefully.
1adjectivelight-headedFaint and unsteady, as if about to lose consciousness.
“She felt light-headed and had to sit down.”
Also accepted in games: dizzy
From light + headed.
Etymology from Wiktionary, CC BY-SA
Practised in A Man Called Ove
First appears in chapter 8 of A Man Called Ove.
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