(adjective) marked by lack of definite plan, regularity, or purpose / (adjective) not connected with the main subject / (adjective) disappointing in progress, performance, or quality
He was also carrying on a desultory conversation with someone on the other end of the telephone
the braying of burros and the desultory tinkling of bells
They talked now in tones which recognized those of the other, and treated with accordingly, desultory tones and cursory remarks which might come close upon but never touch the eventuality which both appeared to await.
Instead, they threw parties that followed a rigid script: first the guys would watch porn while the girls chatted among themselves. When the groups did interact, the guys would make a desultory show of chivalrous ardor, rolling their eyes at one another when they could without the girls noticing