LR or Lr may refer to:
In computer science, LR parsers are a type of bottom-up parser that efficiently read deterministic context-free languages, in guaranteed linear time.
LRRIQ3 (Leucine-rich repeats and IQ motif containing 3), which is also known as LRRC44, is a protein that in humans is encoded by the LRRIQ3 gene.
LRC (short for LyRiCs) is a computer file format that synchronizes song lyrics with an audio file, such as MP3, Vorbis or MIDI.
Low-density lipoprotein receptor-related protein 5 is a protein that in humans is encoded by the LRP5 gene.
Leucine-rich repeat kinase 2 (LRRK2), also known as dardarin (from the Basque word "dardara" which means trembling), is an enzyme that in humans is encoded by the PARK8 gene.
Leucine rich repeat containing 24 is a protein that, in humans, is encoded by the LRRC24 gene. The protein is represented by the official symbol LRRC24, and is alternatively known as LRRC14OS.
Leucine rich repeat containing 57, also known as LRRC57, is a protein that in humans is encoded by the LRRC57 gene.