noun. 1. one who produces or documents an observation. 2. with regard to telepathy experiments, a partaker who is neither the assigned sender nor the assigned receiver. Their job is frequently to protect against experimenter bias or other methodological mistakes.

OBSERVER: "The observers were tired after a full eight-hour day of viewing intermittent changes in the rats' dispositions."
Cite this page: N., Pam M.S., "OBSERVER," in, April 7, 2013, (accessed September 27, 2021).