What does nasty mean?
Nasty is an informal but highly versatile adjective for something unpleasant, offensive, cruel, difficult, or dangerous. It can characterize physical conditions such as a wound, weather, or illness; personal behavior such as cruelty or spite; and actions or events such as a trick, an accident, or a surprise. In modern English, “nasty” is often stronger and more emotionally charged than “unpleasant,” especially when describing a person’s behavior or a cruel act. Its informality gives it an everyday, sometimes emphatic quality, but it can also sound childish or sensational depending on context. The related noun “a nasty” informally denotes an unpleasant, dangerous, or formidable person or thing. Because the adjective covers both tangible discomfort and moral unpleasantness, “nasty” is useful whenever the writer wants to convey more than mild dislike. It is concise, vivid, and emotionally direct, though careful writers may prefer a more specific term.
Unpleasant, offensive, cruel, difficult, or dangerous; objectionable in quality or effect.
"The path was narrow and nasty underfoot."
Informally, an unpleasant, dangerous, or formidable person or thing.
"The final examination was a real nasty."
The plural applies to the informal noun and is chiefly used in everyday speech.
"The film had a couple of real nasties for villains."
Nasty is a compact emotional shortcut: it can condemn bad weather, bad behavior, bad luck, or something genuinely dangerous in a single word.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does nasty come from?
The deeper origin of nasty is uncertain, and no single source can be confidently identified as its ancestor. The word is attested in English by the late sixteenth century, when it was used for qualities that were foul, offensive, or morally objectionable. Its later meanings broadened naturally to cover unpleasant experiences, difficult situations, cruelty, and dangerous conditions.
Related word forms
How nasty is actually used
The adjective is informal and common in everyday speech; it can sound more emphatic or more childish than the more neutral word unpleasant. The noun is chiefly informal and is not normally used in formal writing.