underflow

underflow noun: a current flowing below the surface.

Noun

underflow (countable and uncountable, plural underflows)

A current flowing below the surface.
A condition in which the value of a computed quantity is smaller than the smallest non-zero value that can be physically stored; usually treated as an error condition.
The error condition that results from an attempt to retrieve an item from an empty stack.

underflow (third-person singular simple present underflows, present participle underflowing, simple past and past participle underflowed)

To trigger the condition in which the value of a computed quantity is smaller than the smallest non-zero value that can be physically stored.
To trigger the error condition resulting from attempting to retrieve a value from an empty stack.
- Upon an attempt to pop an empty stack, the stack underflows […]2022, Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, Introduction to Algorithms, fourth edition, page 255

Noun
plural	underflows
Verb
third-person singular present	underflows
present participle	underflowing
past participle	underflowed
past	underflowed

From under- + flow, modelled on overflow.

What does underflow mean?: Underflow means a current flowing below the surface.
What part of speech is underflow?: Underflow can be a noun or a verb.
What is the plural of underflow?: The plural of underflow is underflows.

Adapted from Wiktionary: underflow (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated: 2026-09-02

Pronunciation audio from Wikimedia Commons, each file under its own free license: LL-Q1860 (eng)-Flame, not lame-underflow.wav.

Cite this entry: “underflow.” Word.ws, https://word.ws/underflow. Based on Wiktionary, CC BY-SA 4.0.