Loss

Loss may refer to:

Economic loss
Grief, an emotional response to loss
- Animal loss, grief over the loss of an animal

Mathematics, science, and technology

Angular misalignment loss, power loss caused by the deviation from optimum angular alignment
Bridging loss, the loss that results when an impedance is connected across a transmission line
Coupling loss, the loss that occurs when energy is transferred from one circuit, optical device, or medium to another
Insertion loss, the decrease in transmitted signal power resulting from the insertion of a device in a transmission line or optical fiber
Dielectric loss, a dielectric material's inherent dissipation of electromagnetic energy
Loss function, in statistics, a function representing the cost associated with an event
Path loss, the attenuation undergone by an electromagnetic wave in transit from a transmitter to a receiver
- Free-space path loss, the loss in signal strength that would result if all influences were sufficiently removed having no effect on its propagation
Return loss, the ratio of the amplitude of the reflected wave to the amplitude of the incident wave
Round-trip loss in laser physics refers to energy lost due to scattering or absorption
Switching loss [de], power loss incured due to circuit switching
Lick Observatory Supernova Search (LOSS) program