fluid

B2 Topic:Physics

US /ˈfluɪd/ UK /ˈfluːɪd/ See IPA manual

Freq #5995

Meanings

1

noun
A liquid; a substance that flows.

It is important to drink plenty of fluids when you are ill.
2

adj
Likely to change; not fixed or settled.

The situation is still fluid, so our plans may change.
3

adj
Moving smoothly and gracefully.

The dancer's movements were slow and fluid.

Thesaurus

Synonyms

2 adj · likely to change; not fixed... unstable uncertain

3 adj · moving smoothly and... fluent

More changeable flowing fluidicfluxiveliquid runny variable

Word family

Forms fluidifiedfluids

Derived forms biofluidcorflucryofluidelastofluidferrofluidfluid-bondedfluid-boundfluid-elasticfluid-sfluidarityfluidglyceratefluidification

Related forms fluctuate fluctuation fluency fluentfluidalfluidicfluidicsfluidifyfluidisefluidityfluidizefluidous

Appears in

Phrases (2)

See all

Simplified etymology

Fluid is recorded from Late Middle English and is based on Latin fluere, “to flow.”

Etymology

Etymology tree Proto-Indo-European *bʰel-der. Proto-Indo-European *bʰlewH-der. Proto-Indo-European *bʰluH-yé-ti? Latin fluō Proto-Indo-European *dʰeh₁-der. Latin -idus Latin fluidusder. Middle English fluid English fluid From Middle English fluid, from Latin fluidus (“flowing; fluid”), from Latin fluō (“to flow”), from Proto-Indo-European *bʰleh₁- (“to swell; surge; overflow; run”). Akin to Ancient Greek φλύειν (phlúein, “to swell; overflow”). Not related to English flow, which is a native, inherited word from *plew-, but is distantly related from English bleat.

*bʰel- (blow) Proto-Indo-European fluid Middle English fluidus Latin fluō Latin *bʰleh₁- Proto-Indo-European

View etymology graph ->

Topics

Physics Materials & Substances

External links

# fluid

**Type:** Word
**Level:** B2
**Part of speech:** noun, adj
**IPA (US):** /ˈfluɪd/
**IPA (UK):** /ˈfluːɪd/
**Frequency rank:** 5995

## Meanings
1. A liquid; a substance that flows.
2. Likely to change; not fixed or settled.
3. Moving smoothly and gracefully.

## Examples
- It is important to drink plenty of fluids when you are ill.
- The situation is still fluid, so our plans may change.
- The dancer's movements were slow and fluid.

## Synonyms
- changeable
- flowing
- fluidic
- fluxive
- liquid
- runny
- variable

## Derived Forms
- biofluid
- corflu
- cryofluid
- elastofluid
- ferrofluid
- fluid-bonded
- fluid-bound
- fluid-elastic
- fluid-s
- fluidarity
- fluidglycerate
- fluidification

## Related Forms
- fluctuate
- fluctuation
- fluency
- fluent
- fluidal
- fluidic
- fluidics
- fluidify
- fluidise
- fluidity
- fluidize
- fluidous

## Roots and Affixes
- Root: *bʰel- (blow)
- Root: fluid
- Root: fluidus
- Root: fluō
- Root: *bʰleh₁-

## Etymology
Etymology tree Proto-Indo-European *bʰel-der. Proto-Indo-European *bʰlewH-der. Proto-Indo-European *bʰluH-yé-ti? Latin fluō Proto-Indo-European *dʰeh₁-der. Latin -idus Latin fluidusder. Middle English fluid English fluid From Middle English fluid, from Latin fluidus (“flowing; fluid”), from Latin fluō (“to flow”), from Proto-Indo-European *bʰleh₁- (“to swell; surge; overflow; run”). Akin to Ancient Greek φλύειν (phlúein, “to swell; overflow”). Not related to English flow, which is a native, inherited word from *plew-, but is distantly related from English bleat.

## AI Etymology
Fluid comes from Middle English fluid, from Latin fluidus (“flowing; fluid”), from Latin fluō (“to flow”), from Proto-Indo-European *bʰleh₁- (“to swell; surge; overflow; run”). Akin to Ancient Greek φλύειν (phlúein, “to swell; overflow”). Not related to English flow, which is a native, inherited word from *plew-, but is distantly related from English bleat. In current use, the main senses are “A liquid; a substance that flows” and “Likely to change; not fixed or settled”.

## Topics
- Physics
- Materials & Substances

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