Never Mind or Nevermind :



The standard spelling of this phrase is as two words: “Never Mind.” The popularity of the alternative one-word form “nevermind” was certainly enhanced by its use in 1991 as the title of a bestselling Nirvana album.


“Nevermind” can look immature or slangy to some readers.


You can still be cool by imitating the vocabulary choice in the title of another famous album: Never Mind the Bollocks: Here’s the Sex Pistols.


In expressions like “pay him no nevermind” where the word means “attention” it’s always one word, but those expressions are both slangy and old-fashioned.