functional load

noun2

1. •
   A measure of how much a difference between phonemes disambiguates between different words.

   • The difference between voiced and voiceless TH in English bears a low functional load.
2. •
   Targeted exposure of an implement or organ to stimuli or other straining it is supposed or being tested to tolerate.

   • Here we studied serotoninergic innervation of visceral organs during functional load and under pathological conditions. — 2004