LER or Ler may refer to:
People Larry LaLonde, nicknamed "Ler", guitarist of the rock band Primus Anthony Ler, Singaporean notorious murderer
Places and infrastructure Ler, Norway, a village in the municipality of Melhus in Trøndelag county, Norway Ler, South Sudan, a village in the north central part of South Sudan Leytonstone High Road railway station, a station in London, England Leinster Airport, IATA airport code "LER" London Electric Railway, later part of the London Underground
Science and technology Label edge router, a term used to define an edge-most router in an IP/MPLS network Light-emitting resistor, the working principle of an incandescent light bulb Liquid epoxy resin, a precursor to coatings and flooring material Locus of enterocyte effacement-encoded regulator, a regulatory protein in pathogenic bacteria Luminous efficacy of radiation, for light sources, the ratio of luminous flux to power Lunar Electric Rover, a vehicle designed by NASA for extra-vehicular activity on the lunar surface. Land equivalent ratio, in multicropping or intercropping agriculture, the relative land area needed for the same yield under equivalent disjoint monocultures
Other "Ler" books, a trilogy by M. A. Foster Loss Exchange Ratio, a military calculation of comparative casualties of war The Loyal Edmonton Regiment, an infantry unit of the Army Reserve Canadian Forces Elite One Championship (French: Ligue Élite de Rugby), a French rugby league Ler (mythology), a sea god in Irish mythology also known as Lir