The definition of no-nonsense is a sensible and serious person.
An example of no-nonsense is a bookkeeper who does everything "by the book."
not indulging in or tolerating nonsense, impracticality, etc.; matter-of-fact; practical and serious
Not tolerating irrelevancies; direct, efficient, and practical: the no-nonsense tones of a stern parent; plain, no-nonsense meals at a diner.
(comparative more no-nonsense, superlative most no-nonsense)
- Practical, not concerning oneself with anything silly or unimportant.
- Her no-nonsense way of resolving issues impressed her superiors.