From under- + threshold, probably a calque of German unterschwellig (“subliminal”, literally “under-threshold”), from unter- (“under-”) + Schwelle (“threshold”). More at under, sill.
underthreshold (comparative more underthreshold, superlative most underthreshold)
- Positioned below a threshold.
- Being below the threshold or outside of the ordinary limits of consciousness; subconscious; subliminal.
- 1913, Edward Ebenezer Weaver, Mind and health:
- The notion "underthreshold" is to be explained as all that which is under the ordinary threshold or outside the customary bounds of consciousness; [...]
- 1986, Hormonal ensemble in exercise:
- Accordingly, it represents an underthreshold load in trained persons, and no endocrine response was observed.
- 2003, Vincenzo Capasso, Mathematical modelling & computing in biology and medicine:
- In this way it is possible to describe the underthreshold membrane behavior of a neuron distinguishing the effects of synapses located in the main dendritic tree or near the trigger zone.