Proof has 16 different meanings across 4 categories:
Noun · Verb · Adjective · Proper Noun
any factual evidence that helps to establish the truth of something
"if you have any proof for what you say, now is the time to produce it"
a formal series of statements showing that if one thing is true something else necessarily follows from it
"The mathematician spent years constructing a rigorous proof to demonstrate that the sum of angles in any triangle must equal 180 degrees."
a measure of alcoholic strength expressed as an integer twice the percentage of alcohol present (by volume)
"The bartender corrected the label, noting that the whiskey's 100 proof actually meant it contained only fifty percent alcohol by volume."
(printing) an impression made to check for errors
"The editor carefully reviewed every proof before approving it for mass printing."
a trial photographic print from a negative
"The photographer held up the proof to check if the exposure was correct before making additional prints."
the act of validating; finding or testing the truth of something
"We spent hours trying to find proof that the new algorithm actually reduces energy consumption before launching it."
An effort, process, or operation designed to establish or discover a fact or truth; an act of testing; a test; a trial.
"The lab technician conducted a rigorous proof on the new vaccine formula before approving it for public use."
In plain English: Proof is solid evidence that something is true or real.
"The teacher asked for proof that you had completed your homework before grading it."
Usage: Use proof when referring to evidence that establishes a fact or the result of a test, such as scientific proof or proof of a concept. Avoid using it for mere suspicion or assumption, which should be described as evidence or indication instead.
make or take a proof of, such as a photographic negative, an etching, or typeset
"The photographer took a proof before deciding whether to develop all the negatives for the wedding album."
To proofread.
"I need to proofread the entire manuscript before submitting it for publication."
In plain English: To prove something means to show that it is true by giving evidence or reasons.
"The detective presented proof that the suspect was not at the scene of the crime."
Usage: To proof in its traditional sense means to test or verify something, such as testing the strength of a material or checking if a substance is effective. However, in modern everyday usage, people often mistakenly use "proof" as a verb when they mean to "proofread," which is the correct term for checking text for errors.
Used in proving or testing.
"The mechanic asked for a proof of concept before installing the new engine software on our fleet."
In plain English: Proof means something is absolutely true and cannot be argued with.
"The proof reading took place before the final print run."
Usage: Use "proof" as an adjective to describe something that has been tested to verify its truth or reliability, such as proof of concept or proof of payment. Avoid using it to mean "evidence" itself, which requires the noun form.
The 98th sura (chapter) of the Qur'an.
"While many Muslims consider Surah Al-Baqarah to be the longest chapter, some traditions also refer to the 98th sura as proof in their recitation lists."
The word proof comes from the Latin verb probō, meaning "to prove," and entered Middle English via Old French as a noun for evidence or verification. It traveled into modern usage with its core meaning intact, though it is related to the doublet probe.