Synonyms of no-nonsense

1 Syllable
hard, staid, bluff, strict, stern
2 Syllables
staidest, solemn, bluffer, bluffed, grave, serious, direct, graver, rigid, stricter, gravest, strictest, somber, staider
3 Syllables
demanding, dead-level, sedate, practical, efficient, long-faced, sincere, unsmiling, grim-faced, down-to-earth, sincerest, hard-nosed
4 Syllables
unhumorous
5 Syllables
businesslike