A house made up of two dwelling units.

A cancellation combining a numerical cancellation with a second mark showing time, date, and place of posting.

A throwing motion where two balls are thrown with one hand at the same time.

To make duplex.

To make into a duplex.

(juggling) To make a series of duplex throws.

Double, made up of two parts.

Bidirectional (in two directions).

“duplex telegraphy”

Having horizons with contrasting textures.