Real Dictionary

catwalk
At a fashion show, the catwalk is a narrow platform that models walk along to display clothes.
countable noun: A catwalk is a narrow bridge high in the air, for example between two parts of a tall building, on the outside of a large structure, or over a stage.

catwalk in American English
a narrow, elevated walk or platform, as one along the edge of a bridge or over the engine room of a ship
noun: a narrow walkway, esp. one high above the surrounding area, used to provide access or allow workers to stand or move, as over the stage in a theater, outside the roadway of a bridge, along the top of a railroad car, etc

catwalk in British English
noun: a narrow ramp extending from the stage into the audience in a theatre, nightclub, etc, esp as used by models in a fashion show

catwalk in the Oil and Gas Industry
noun: A catwalk is a long, rectangular platform below the vee-door and slide, used for receiving, storing, or preparing rig and drill string tools.