Wiktionary
unspontaneous
a. Not spontaneous; halting or rehearsed
Usage examples of "unspontaneous".
Kurtz had become, but because he saw it as a trespass, an unspontaneous and self-conscious venture into the rites of an alien species.
She was, Marion saw, looking at her again under faintly contracted brows, and she realised that because she wept about the child at Coltsfoot her eyes were small and red, and that had added to her face a last touch of ruin which made it an unfavourable place for the struggles of an unspontaneous expression of amiability.
She laughed gently, but it sounded unspontaneous enough to put me on my guard.