In psychodynamics, psychic negentropy refers to mental states of positive emotions such as happiness, strength, or alertness. [1] The term seems to have been first introduced in 1986 by Hungarian-born American psychologist Mihály Csíkszentmihályi, a syncretism of the older terms psychic entropy (1928) + negentropy (1942), literally meaning “negative psychic entropy”. [2]

References
1. Albert, Robert S. (1992). Genius and Eminence (pg. 30). Routledge.
2. (a) Csíkszentmihályi, Mihály and Larson, Reed. (1986). Being Adolescent: Conflict and Growth in the Teenage Years (section: Negentropy: Order in the Consciousness, pg. 23). Basic Books.
(b) Csíkszentmihályi, Mihály. (1997). Finding Flow: the Psychology of Engagement with Everyday Life (pg. 22). Basic Books.