velocity

noun

ve·​loc·​i·​ty və-ˈlä-sə-tē 

-ˈlä-stē

plural velocities

1

a

: quickness of motion : speed

the velocity of sound

b

: rapidity of movement

[my horse's] strong suit is grace & personal comeliness, rather than velocity

—Mark Twain

c

: speed imparted to something

The power pitcher relies on velocity …

—Tony Scherman

2

: the rate of change of position along a straight line with respect to time : the derivative of position with respect to time

3

a

: rate of occurrence or action : rapidity

… the velocity of historical change …

—R. J. Lifton

b

: rate of turnover

the velocity of money

Synonyms of velocity

• speed
• rate

Examples of velocity in a Sentence

particles moving at high velocities

measuring the velocity of sound

the velocity of a bullet

Recent Examples on the Web

Many of the heaviest elements arise only in environments where lots of free neutrons crash into atomic nuclei at great velocities. — Robin George Andrews, Scientific American, 20 Oct. 2026

The simulations use particles to trace dark matter’s density and velocity, allowing scientists to model how cosmic structures evolved. — Kaif Shaikh, Interesting Engineering, 20 Oct. 2026

Another has chosen maximum velocity over protection, with deregulation that serves interests well beyond its technology sector. — Juan Carlos Santiago, Forbes.com, 20 Oct. 2026

That’s because the rocket aims for full reusability, with a novel upper stage thruster design and heat shield to solve the difficult problem of protecting a vehicle reentering at orbital velocity. — Eric Berger, ArsTechnica, 20 Oct. 2026

Word History

Etymology

Middle English velocite, borrowed from Anglo-French & Latin; Anglo-French veloceté, borrowed from Latin vēlōcitāt-, vēlōcitās, from vēlōc-, vēlōx "swift, rapid" (of uncertain origin) + -itāt-, -itās -ity

Note: If going back to earlier *ueg-s-l-o-, perhaps a derivative from the base of vegēre "to give vigor to, enliven" (see vegetate) or vehere "to convey" (Indo-European *u̯eǵh-; see vehicle), assimilated to the -ōk- of ātrōx, ferōx (see atrocious, ferocious). Alternatively, a derivative *uē-lo-, from the Indo-European base *h₂u̯eh₁- "blow" (hence, "windlike"; see wind entry 1) has been suggested.

First Known Use

15th century, in the meaning defined at sense 1a

Phrases Containing velocity

• angular velocity
• escape velocity

Rhymes for velocity

• atrocity
• ferocity
• monstrosity
• pomposity
• porosity
• precocity
• schistosity
• verbosity
• viscosity
• animosity
• curiosity
• generosity

Kids Definition

velocity

noun

ve·​loc·​i·​ty və-ˈläs-ət-ē 

-ˈläs-tē

plural velocities

1

: quickness of motion : speed

the velocity of sound

2

: the rate of change of position along a straight line with respect to time

3

: rate of occurrence or action

the velocity of political change