unprepossessing

adjective

1. that impresses favorably; engaging or attractive: a confident and prepossessing young man.

adjective

1. not creating a favourable impression; unattractive

adjective

1. creating a favourable impression; attractive

adj.1816, from un- (1) “not” + prepossessing. adj.1640s, “causing prejudice,” present participle adjective from prepossess. Opposite meaning “causing agreeable first impression” first recorded 1805.