2. Adjective. (British slang) Considered to be poor taste. ¹
3. Adjective. (context: Polari) Bad; tasteless. ¹
4. Adjective. (British slang) Something that is poorly thought out, doesn’t really work, or is otherwise not very good. ¹
5. Adjective. (context: Polari) Heterosexual. ¹
¹ Source: wiktionary.com
Definition of Naff
1. to fool around [v -ED, -ING, -S]