brainstorm

Short definition from Wiktionary

Verb

1. 1
   To investigate something, or solve a problem using brainstorming.
2. 2
   To participate in a brainstorming session.
3. 3
   To think up (ideas); especially, to do so creatively.

Noun

1. 1
   A sudden thought, particularly one that solves a long-standing problem.
2. 2
   A session of brainstorming, investigating a problem to try to find solutions.
3. 3
   An unexpected mental error.
4. 4
   Alternative form of brain storm (“activity in the brain, such as a seizure or convulsion”).