“Heads-up” is informal advance warning, advice or information that lets someone prepare. Cambridge also records the short warning expression, so the guide separates the noun phrase from the direct exclamation instead of treating every “heads up” identically.
ReviewedEvidence1 sourceSectionPhrases & Idioms
Quick answer
A “heads-up” is an informal warning or advance notice that helps someone prepare. “Give someone a heads-up” is the common noun pattern; “Heads up!” can also function as a warning expression.
Key details
Canonical FormHeads Up
Core Meaningan informal warning, piece of advice or advance information that helps someone prepare
Registerinformal
Further guidance
History Boundary
This guide makes no unsupported coinage or first-use claim; it publishes the supported current meaning and usage boundary.
Meaning
Use “give someone a heads-up” for advance notice in informal or neutral communication. The hyphenated noun form is useful when the expression functions as a thing being given.
Usage Boundary
Because the expression is informal, a formal document may prefer “advance notice,” “warning” or “notification” when tone matters.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
“Go Belly Up” means for a company or plan to fail. It is informal and is especially common for business failure or a plan that collapses, so use a more neutral verb such as “fail” in formal contexts when needed.
“Up in the air” describes a matter whose outcome or decision remains uncertain, often because other issues still have to be settled. This guide records the current dictionary meaning without asserting an exact origin date.
“A blessing in disguise” describes something that initially seems bad or unlucky but later produces a good result. Specialist history places the printed phrase in the mid-eighteenth century, while earlier texts may express similar ideas without proving the same idiom.
The informal idiom “not have a snowball’s chance in hell” describes a situation with essentially no chance of success. This guide limits the page to the current form, register, and meaning supported by Cambridge and does not add an unsupported origin story.
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