use or exercise the mind or one's power of reason in order to make inferences, decisions, or arrive at a solution or judgments

the concentration of attention or energy on something

the object upon which interest and attention focuses

devote (oneself) fully to

cause one's (or someone else's) thoughts or attention to return from a reverie or digression

focus one's attention on a certain state

examine closely; focus one's attention on

listen and pay attention

hold (someone's attention)