operandum

English Noun

Definition

A lever, key or device installed in an operant chamber, upon which the "subject" exerts its responses. Sometimes referred to as a manipulandum. In the prototypical operant conditioning experiment, a rat (the subject) presses upon a lever (the operandum) which triggers the delivery of food (the reward or reinforcer).

Etymology

From Latin operandum. Doublet of operand.