un·hu·mor·ous
| \ ˌən-ˈhyüm-rəs
, -ˈyüm-, -ˈhyü-mə-, -ˈyü-\
: not amusing or humorous
an unhumorous subject The other joke is that Joseph Miller, though a competent comic actor, was in person taciturn and utterly unhumorous.— D. J. Enright