noun, verb ·Uncommon ·Advanced level

Definitions

Noun

1. 1
   The flow of a fluid (through a pipe etc.) in a direction opposite to that which is normal or intended. countable, uncountable
2. 2
   a flow that returns toward its source wordnet

Verb

1. 1
   To flow in the wrong or backward direction. intransitive, transitive

Synonyms

All synonyms

back streambackflowingbackfluxbackfluxbackwashbackwater

Etymology

From back + flow.

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