double (part of speech: adjective)
duplication (part of speech: noun)
- Full- duplex is simultaneous two- way communication. - "The Online World", Odd de Presno.
- Slide rests for self- acting or engine lathes are divided into seven kinds, termed respectively as follows: simple, or single, elevating, weighted, gibbed, compound, duplex, and duplex compound. - "Modern Machine-Shop Practice, Volumes I and II", Joshua Rose.
- So still was the atmosphere, so unruffled the water, that the island and the piratical- looking schooner seemed to float in the centre of a duplex world, where every cloudlet in the blue above had its exact counterpart in the blue below. - "The Madman and the Pirate", R.M. Ballantyne.