'non-stimulatory' originates from Latin and English elements: the prefix 'non-' (from Latin 'non', meaning 'not') prefixed to 'stimulatory' (from Latin 'stimulus'/'stimulare' via English 'stimulate').

'stimulatory' derives from Medieval/Modern English formation from 'stimulate' + the adjective-forming suffix '-ory'; 'stimulate' comes from Latin 'stimulare' (to goad, urge) based on 'stimulus' (a goad). The negative form 'non-stimulatory' is a Modern English formation by adding the prefix 'non-' to the adjective.

Originally the Latin root related to a physical 'goad' or incentive ('stimulus'); over time English formed 'stimulatory' to mean 'causing stimulation,' and 'non-stimulatory' came to mean 'not causing stimulation' in physiological, pharmacological, or psychological contexts.