reinforcement

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The act or process of reinforcing or the state of being reinforced.
2. n. Something that reinforces.
3. n. Additional personnel or equipment sent to support a military action. Often used in the plural.
4. n. Psychology The occurrence or experimental introduction of an unconditioned stimulus along with a conditioned stimulus.
5. n. Psychology The strengthening of a conditioned response by such means.
6. n. Psychology An event, a circumstance, or a condition that increases the likelihood that a given response will recur in a situation like that in which the reinforcing condition originally occurred.

Century Dictionary and Cyclopedia

1. n. The act of reinforcing.
2. n. Additional force; fresh assistance; specifically, additional troops or forces to augment the strength of a military or naval force.
3. n. Any augmentation of strength or force by something added.
4. n. Splints of rigid material built into a compound or sinew-backed bow.

Wiktionary

1. n. uncountable The act, process, or state of reinforcing or being reinforced.
2. n. countable A thing that reinforces.
3. n. in the plural Additional troops or materiel sent to support a military action.
4. n. uncountable The process whereby a behavior with desirable consequences comes to be repeated.

GNU Webster's 1913

1. n. See reënforcement.

WordNet 3.0

1. n. information that makes more forcible or convincing
2. n. a military operation (often involving new supplies of men and materiel) to strengthen a military force or aid in the performance of its mission
3. n. a device designed to provide additional strength
4. n. (psychology) a stimulus that strengthens or weakens the behavior that produced it
5. n. an act performed to strengthen approved behavior