v.

act, feel, or give mutually or in return

"We always invite the neighbors and they never reciprocate!"

alternate the direction of motion of

"the engine reciprocates the propeller"

Opposing BOLD responses to reciprocated and unreciprocated altruism in putative reward pathways
Reciprocated matrix metalloproteinase activation: a process performed by interstitial collagenase and progelatinase A.
ORDER BISPECTRUM: A NEW TOOL FOR RECIPROCATED MACHINE CONDITION MONITORING
Oscilating head cleaner
Stability and Change in Peer Relationships during the Transition to Middle-Level School.
Group identification in early adolescence: its relation with peer adjustment and its moderator effect on peer influence
Prioritizing User-Session-Based Test Cases for Web Applications Testing
Reciprocity and interchange of grooming and "support"in captive chimpanzees.
Reciprocal and Nonreciprocal Social Support: Contrasting Sides of Intimate Relationships
Preliminary observations on breeding and rearing the seahorse Hippocampus abdominalis (Teleostei: Syngnathidae) in captivity