To generate an idea.
To apprehend in thought so as to fix and hold in the mind; to memorize.
Produced by an idea.
The actual existence supposed to correspond with an idea; the correlate in real existence to the idea as a thought or existence.
To create in one's mind; to originate an idea through thought.
Used other than figuratively or idiomatically: see think, of. (to think on the subject of)