Green’s Dictionary of Slang

lol phr.

also lolz
[orig. used in instant messaging; abbr. laughing out loud]

an expression of amusement or approval.

[US]C. Eble UNC-CH Campus Sl. Spring 2014.
[US]J. Bacharach Bend of World 298: I texted Lauren Sara: funeral is fucked. She replied right away: where’s tom? up front, I replied. LOL, she said: figurz.
[US]Woods & Soderburg I Got a Monster 133: ‘This has been ass lol,’ Harris responded. ‘U telling me. Lol’ .