thought

(verb): To ponder, to go over in one's head.
(verb): To communicate to oneself in one's mind, to try to find a solution to a problem.
(verb): To conceive of something or someone (usually followed by of; infrequently, by on).
(verb): To be of opinion (that); to consider, judge, regard, or look upon (something) as.
(verb): To guess; to reckon.
(verb): To plan; to be considering; to be of a mind (to do something).
(verb): To presume; to venture.
(verb): To seem, to appear.
(noun): Form created in the mind, rather than the forms perceived through the five senses; an instance of thinking.
(noun): The operation by which such forms arise or are manipulated; the process of thinking; the agency by which thinking is accomplished.
(noun): A way of thinking (associated with a group, nation or region).

Idly, the detective thought what his next move should be.
I thought for three hours about the problem and still couldn’t find the solution.
I tend to think of her as rather ugly.
At the time I thought his adamant refusal to give in right.
I think she’ll pass the examination.