Fluent is an adjective related to fluency, the ability to communicate in a language quickly and accurately.

Fluent or fluency may also refer to: Fluent (mathematics), in mathematics, a continuous function Fluent (artificial intelligence), in artificial intelligence, a condition that varies over time Fluent calculus, a formalism for manipulating fluents Fluent, Inc., a company that develops software for computational fluid dynamics Fluent interface, a software engineering object-oriented construct Fluent (user interface), introduced in the 2007 Microsoft Office system Fluent Design System, a design language developed by Microsoft in 2017 Fluentd, open source data collection software Fluency (handwriting), an aspect of handwriting ability

See also Fluenz (language learning software), a digital language learning platform