a thing that connects two things, especially mechanical components or systems:a hydraulic coupler
Music a device in an organ for connecting two manuals, or a manual with pedals, so that they both sound when only one is played.
(also octave coupler) Music a device in an organ for connecting notes with their octaves above or below.
Photography a compound in a developer or an emulsion which combines with the products of development to form an insoluble dye, part of the image.
(also acoustic coupler) a modem which converts digital signals from a computer into audible sound signals and vice versa, so that the former can be transmitted and received over telephone lines.
coupler in other Oxford dictionaries
Definition of coupler in the US English dictionary
