nightdream

plural nightdreams

1. A dream that is experienced while sleeping at night, as distinguished from a daydream.First known use 16th c.

   SEBAS-A variables pertinent to sexual orientation covered […] romantic/sexual daydreams, romantic/sexual nightdreams, […].

   2007 December 22, Heino F. L. Meyer-Bahlburg et al., “Sexual Orientation in Women with Classical or Non-classical Congenital Adrenal Hyperplasia as a Function of Degree of Prenatal”, in Archives of Sexual Behavior, volume 37, number 1, →DOI

   1 more example

   You have black nightdreams, I know, for I have sat by you as you slept and heard you talk and seen your terror, which would soon destroy you if you could recall it, as one night showed.

   1937, Fritz Leiber, The Terror from the Depths