sombreUK
seriousShe had a serious look on her face.
earnestAt that time he was an earnest young environmental activist.
soberThe mood of the gathering was sober and reflective.
solemnThe two men fell silent, their faces solemn.
grimHe looked over at Ed, his expression grim.
unsmilingI was greeted by her terse unsmiling face.
stone-facedUSHe listened stone-faced as the verdict was read out.
dourDespite the dour demeanor, he can laugh at himself.
humorlessUSThey are a notoriously humorless bunch.
po-facedUKinformaldisapprovingPeople sometimes think of the world of classical music as being po-faced, but the opposite is true.