1776, "functional derangement arising from disorders of the nervous system (not caused by a lesion or injury)," coined by Scottish physician William Cullen (1710-1790) from Greek neuron "nerve" (see neuro-) + Modern Latin -osis "abnormal condition." Originally of epilepsy, hysteria, neuralgia, etc. Used in a general psychological sense from 1871, "change in the nerve cells of the brain resulting in symptoms of stress," but not radical loss of touch with reality (psychosis); clinical use in psychiatry dates from 1923.
1775, "acting upon or stimulating the nerves," from Greek neuron "nerve" (see neuro-) + -otic, as in hypnotic. Also compare neurosis. Meaning "relating to the nervous system" is by 1873. Sense of "affected by or prone to neurosis" is by 1887. The noun meaning "a neurotic person" is from 1896; earlier it meant "a drug acting on the nerves" (1660s). Related: Neurotically.
c. 1600, "belonging to the earliest age or stage," from Medieval Latin primalis "primary," from Latin primus "first" (see prime (adj.)). Psychological sense, in reference to Freud's theory of behaviors springing from the earliest stage of emotional development, is attested from 1918. Primal scream in psychology is from a best-selling book of 1971 (Arthur Janov, "The Primal Scream. Primal Therapy: The Cure for Neurosis"). Related: Primality.
early 15c., "coercion, application of force (to someone) overwhelming his preferences," from Old French compulsion, from Latin compulsionem (nominative compulsio) "a driving, urging," noun of action from past-participle stem of compellere "to drive, force together," from com "with, together" (see com-) + pellere "to drive" (from PIE root *pel- (5) "to thrust, strike, drive").
Psychological sense of "instant impulse to behave in a certain way" is from 1909 in A.A. Brill's translation of Freud's "Selected Papers on Hysteria," where German Zwangsneurose is rendered as compulsion neurosis.