défaillir

The French verb "défaillir" means to faint, lose strength, or fail physically or mentally. It is often used to describe a sudden loss of consciousness or a moment of weakness.

Meanings:

1. To faint or lose consciousness: For example, "Elle a failli défaillir de peur" (She almost fainted from fear).
2. To fail or weaken: This can refer to strength, courage, or heart, e.g., "Son courage a commencé à défaillir" (His courage began to fail).
3. To give out or fail mechanically: Sometimes used in a broader sense for something malfunctioning or not working correctly, although less common.

Synonyms and their differences:

• S'évanouir: Specifically means "to faint" or "to lose consciousness." It is a direct synonym for "défaillir" in the sense of fainting and is more neutral.
• Tomber dans les pommes: An idiomatic colloquial expression meaning "to pass out" or "faint," informal.
• Faiblir: Means "to weaken" or "grow weak," often in a gradual sense, while défaillir can imply more sudden or critical failure.
• Perdre connaissance: Literally "to lose consciousness," a more formal or clinical expression for fainting.

In summary, "défaillir" often implies a sudden physical or mental failure, especially fainting, and can be more intense or dramatic compared to some synonyms.