The most common postwar slang term for Japanese people in U.S. usage was “Jap” , but it is a slur and generally considered offensive today. A less common term you may also see is “Nip” , which is also derogatory.

What it means

  • Jap : shortened from “Japanese,” used as a racial slur in wartime and after WWII.
  • Nip : another ethnic slur for people of Japanese descent, from “Nippon”.
  • In historical discussions, people may also mention “honcho” as a Japanese-derived word that entered U.S. slang after the war, but it means “boss/leader,” not a label for Japanese people.

Important note

If you are asking for the nickname Japanese people used for Americans after the war , a common neutral term was “Ami” or “Amis” , short for American.

Safer wording

In modern writing, use “Japanese Americans,” “Japanese people,” or “people of Japanese descent” instead of older slang terms.

In short: the postwar slang you’re probably thinking of is “Jap” , but it’s offensive; for the Japanese term for Americans, “Ami/Amis” is the better answer.