adj, noun ·Rare ·Advanced level

Definitions

Noun

1. 1
   Absence of return; failure to come back or bring back. uncountable

Adjective

1. 1
   Allowing air or liquid to travel in one direction only, and not permitting its return. (of a valve) not-comparable

Etymology

From non- + return.

Related phrases

non return

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.