The abbreviation LM or lm may refer to:
Lamin A/C also known as LMNA is a protein that in humans is encoded by the LMNA gene. Lamin A/C belongs to the lamin family of proteins.
No.5551 The Unknown Warrior is a steam locomotive which is under construction as a "new-build" project, based on the Llangollen Railway in Denbighshire, Wales.