Kilroy was here

English

"Kilroy" figure and "Kilroy was here" text, inscribed on the World War II Memorial in Washington, D.C.

Phrase

Kilroy was here

2. (military, c. 1940s) Inserted in the manner of graffiti in many remote and difficult-to-access locations to mark the presence of American workers or military personnel.
3. (meme, late 20th c., non-military) Graffiti scrawled by random anglophones in random locations, with no associations or connotations

References

• Douglas Harper (2001–2024) “kilroy”, in Online Etymology Dictionary.