Now used as the abbreviation for "Laughing out Loud," was previously used in the medical field, especially by interns, to stand for "Little Old Lady." Used in the classic medical school novel, In the House of God.
Nurse: Mrs. Smith, 87, diabetes, cataracts, CAD, CHF, dizziness. Fell and broke her hip when she tripped on her cat.
Intern: Typical LOL.