ˈlimən ə l, ˈlīm- adjective
Etymology: International Scientific Vocabulary limin- (from Latin limin-, limen threshold) + -al — more at limen
1. : of or relating to the limen
liminal research
2. : situated at the limen : barely perceptible
observation of liminal hues is beset with difficulties — Elsie Murray
3. : having the lowest amount necessary to produce a particular effect : possessing the minimal quantity
an electron must be given a certain liminal amount of energy before it can escape from the metal — Therald Moeller