The word recumbent is an adjective. Recumbent means (1) lying down; in a position of comfort or rest.
The following articles and web pages elaborate on the word recumbent.
Recumbent Bikes
A recumbent bicycle features pedals that are roughly the same height as the seat and is ridden from a reclined position. Recumbent bike proponents claim these bicycles are safer to ride.
https://www.Recumbent-Bikes.us/
Recumbent Bicycle History
Recumbent bicycles allow the rider to sit in a reclined position instead of erect while pedaling. Learn about the history of recumbent bikes and find links to manufacturers and dealers.