noun
stack
stak
noun
1
A pile of things placed neatly one on top of another.
"He balanced a stack of plates on one arm."
"There's a stack of unread mail on the counter."
2
In computing, a data structure where the last item added is the first one removed, or the memory area used for tracking function calls.
"The program crashed with a stack overflow error."
"Each function call pushes a new frame onto the stack."
3
Informal: a large sum of money.
"She made stacks of cash flipping houses."
verb
1
To arrange things in a pile, or to add something to an existing pile.
"Stack the chairs against the wall after the meeting."
"They stacked sandbags along the riverbank."
How to Use Stack
Learner’s notesIn plain EnglishThings piled on top of each other — or, in tech, a particular way of storing and retrieving data or software layers.
Common mistake
In casual speech "to stack" can also mean to crash (e.g. a bike), which can confuse readers expecting the "pile up" sense.
Common pairings
a stack of papers
stack overflow
tech stack
stack up
Word Forms
stacked past tense, stacks plural, stacks singular
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He balanced a _____ of plates on one arm.
Etymology
From Old Norse stakkr, meaning a haystack or heap; the computing sense is a much later, figurative extension of the same "pile" idea.