OTR

Otr or OTR may refer to:

• Ótr, a dwarf in Norse mythology
• Otr, the abbreviation for the orchid genus Otaara
• The IATA code for Coto 47 Airport, an airport that serves Coto 47, Costa Rica

OTR may refer to:

• Optical Transition Radiation, in physics, the radiation emitted by a charged beam at the interface between two mediums
• Oxygen transmission rate, a measure of a barrier material's oxygen permeability
• Organisation and Technology Research (OTR plc), a European information technology research company
• Over-the-Rhine, the Cincinnati, USA neighborhood
• On the Run (convenience store), an international convenience store chain owned by ExxonMobil
• Off-the-road tires, for construction or mining vehicles

In media:

• Old-time radio, or "Golden Age Radio", a term describing an era of radio programmes in the first half of the 20th century
• Off The Record (TSN TV series), a Canadian sports talk show

In computers

• Off-the-Record Messaging, an instant messaging encryption system

In finance

• On the run (finance), used to describe the most recently issued security

In music:

• On The Rocks (band), a rock band featuring British, Dutch and Brazilian members
• Over the Rhine (band), an Ohio, USA based band
• Otierre or OTR (Originale Trasmissione del Ritmo), an Italian hip hop band