think
noun
an instance of deliberate thinking
“I need to give it a good think”
verb
judge or regard; look upon; judge
“I think he is very smart”
“I believe her to be very smart”
expect, believe, or suppose
“I imagine she earned a lot of money with her new novel”
“I thought to find her in a bad state”
use or exercise the mind or one's power of reason in order to make inferences, decisions, or arrive at a solution or judgments
“I've been thinking all day and getting nowhere”
recall knowledge from memory; have a recollection
“I can't remember saying any such thing”
“I can't think what her last name was”
imagine or visualize
“Just think--you could be rich one day!”
“Think what a scene it must have been!”
focus one's attention on a certain state
“Think big”
“think thin”
have in mind as a purpose
“I mean no harm”
“I only meant to help you”
decide by pondering, reasoning, or reflecting
“Can you think what to do next?”
ponder; reflect on, or reason about
“Think the matter through”
“Think how hard life in Russia must be these days”
dispose the mind in a certain way
“Do you really think so?”
have or formulate in the mind
“think good thoughts”
be capable of conscious thought
“Man is the only creature that thinks”
bring into a given condition by mental preoccupation
“She thought herself into a state of panic over the final exam”
Source: WordNet 3.1, Princeton University