1. 晕厥；暂时昏迷
If you black out, you lose consciousness for a short time.
2. 对…实行灯火管制；使一片漆黑
If a place is blacked out, it is in darkness, usually because it has no electricity supply.
3. 禁播（电影等）；禁止发行，禁止出版（文章、图书等）
If a film or a piece of writing is blacked out, it is prevented from being broadcast or published, usually because it contains information which is secret or offensive.
4. 涂黑，盖住，涂掉（文字等）
If you black out a piece of writing, you colour over it in black so that it cannot be seen.
5. 尽力忘记；努力忘却
If you black out the memory of something, you try not to remember it because it upsets you.
1. lose consciousness due to a sudden trauma, for example
2. suppress by censorship as for political reasons
e.g. parts of the newspaper article were blacked out
3. darken completely
e.g. The dining room blackened out
Synonym: blacken out
4. obliterate or extinguish
e.g. Some life-forms were obliterated by the radiation, others survived