molecule

noun

mol·​e·​cule ˈmä-li-ˌkyül 

1

: the smallest particle of a substance that retains all the properties (see property sense 1a) of the substance and is composed of one or more atoms (see atom sense 1a)

a molecule of water

a molecule of oxygen

2

: a tiny bit : particle

a molecule of political honesty

—Time

Synonyms

• atom
• bit
• crumb
• dribble
• fleck
• flyspeck
• grain
• granule
• morsel
• mote
• nubbin
• nugget
• particle
• patch
• scrap
• scruple
• snip
• snippet
• speck
• tittle

Examples of molecule in a Sentence

There is not a molecule of evidence to support these charges.

not a molecule of sense in that girl

Recent Examples on the Web

The particles interact with molecules of atmospheric gases to cause the famed glowing green and reddish colors of the aurora. —Doyle Rice, The Enquirer, 10 May 2024

But eventually, the same molecules of lithium and nickel could be used for many generations of cars – something that can't be said for fossil fuels. —Camila Domonoske, NPR, 9 May 2024

Word History

Etymology

French molécule, from New Latin molecula, diminutive of Latin moles mass

First Known Use

1701, in the meaning defined at sense 1

Kids Definition

molecule

noun

mol·​e·​cule ˈmäl-i-ˌkyü(ə)l 

1

: the smallest particle of a substance having all the characteristics of the substance

a molecule of water

a molecule of oxygen

2

: a very small bit : particle

Medical Definition

molecule

noun

mol·​e·​cule ˈmäl-i-ˌkyü(ə)l 

: the smallest particle of a substance that retains all the properties of the substance and is composed of one or more atoms