reciprocation

n. act of requiting, act of doing something in return

See Reciprocal for mathematical terminology.Reciprocation is the action in which a body's displacement returns to its starting location in a given time repeatedly. The velocity over which the displacement occurs with each repetition not necessarily being constant. Such an action is usually used to describe quickly moving implements in mechanical objects usually linealy within a given axis, or even in complex displacement/velocity paths. eg. the Piston engine is a Reciprocating Engine with the Piston being the object of reciprocation within the linealy axis of the cylinder.
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Noun
1. the act of making and return or doing something in return
(hypernym) return, paying back, getting even
(derivation) reciprocate
2. alternating back-and-forth movement
(hypernym) motion, movement, move, motility
(derivation) reciprocate
3. mutual interaction; the activity of interchanging or reciprocating
(synonym) interchange, give-and-take
(hypernym) interaction
(hyponym) reciprocity
(derivation) reciprocate

(n.)
The act of reciprocating; interchange of acts; a mutual giving and returning; as, the reciprocation of kindnesses.
  

(n.)
Alternate recurrence or action; as, the reciprocation of the sea in the flow and ebb of tides.
  

n.
the act
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