What does LUL stand for?

Language, Unseamanlike - Slang - Military (DNAB)

Laurel, MS - Location identifier - FAA (FAAL)

Left Upper Eyelid - Medicine

Left Upper Lid (SAUS)

Left Upper Limb - Medicine

Left Upper Lobe - of lung - Medicine

London Underground Limited - Electric railway system (UKR)

London Underground Ltd. - British

London University Library (SAUO)

Olu'bo - Language code (ETLW)