vacilar

Senses

1. 1.

   to hesitate, to waver

   to be uncertain or indecisive about something

2. 2.

   to slip up, to mess up

   to make a mistake or fail to act properly (colloquial)

3. 3.

   to falter, to stumble

   to lose balance or stability, physically or figuratively

Examples

• "Não vacila na hora de tomar a decisão."

  Don't hesitate when it's time to make the decision.

• "Se você vacilar, vão te passar para trás."

  If you slip up, they'll get ahead of you.

• "Ele vacilou no palco e quase caiu."

  He stumbled on stage and almost fell.

Usage

Very common in colloquial Brazilian Portuguese, especially in the sense of "making a mistake" or "losing focus." Often used in warnings like "não vacila!" (don't mess up!). In some contexts, can mean to show off or act foolishly, though this is more regional.