To strengthen or support an object or structure, especially with additional material. The builders reinforced the bridge with steel beams to ensure it could withstand heavy traffic.
To make a feeling, idea, or habit stronger or more pronounced. The teacher used positive feedback to reinforce the students' confidence in their abilities.
To send additional troops or resources to support a military force. The general decided to reinforce the front lines with more soldiers to prepare for the upcoming battle.
(Psychology) To encourage the repetition of a response by presenting a reward or other positive stimulus after the response. The trainer reinforced the dolphin's jump with a fish.