Absolute Threshold

n. (Psychology) lowest level of a stimulus that one can detect, minimum point at which a stimulus is strong enough to produce an effect

A term often used in neuroscience and experimental research. An absolute threshold is the smallest detectable level of a stimulus. For example, in an experiment on sound detention, researchers may present a sound with varying levels of volume. The smallest level that a participant is able to hear is the absolute threshold.
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Noun
1. the lowest level of stimulation that a person can detect
(hypernym) threshold, limen
(hyponym) pain threshold

the minimum/ maximum stimulation (sight, sound, smell, taste, touch) needed to detect a particular stimulus.