- (astrophysics) Abbreviation of Lagrange point 3, located 180 degrees away from the smaller object and slightly outside the smaller object's orbit around the larger object.
- (astrophysics): Lagrange point, L1, L2, L4, L5
From Level 3.
- (computing) Short for third level in various contexts
- (computing) The third-level cache of a processor, farther away from the processor than the second-level cache.
- (networking) The network layer in the seven-layer OSI network model.
- an L3 switch