noun, verb ·Rare ·Advanced level

Definitions

Noun

1. 1
   A current flowing below the surface. countable, uncountable
2. 2
   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. countable, uncountable
3. 3
   The error condition that results from an attempt to retrieve an item from an empty stack. countable, uncountable

Verb

1. 1
   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.
2. 2
   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 […]"

Antonyms

All antonyms

overflow

Example

More examples

"Upon an attempt to pop an empty stack, the stack underflows […]"

Etymology

From under- + flow, modelled on overflow.

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.