a rule or standard especially of good behavior
"a man of principle"
"he will not violate his principles"
A fundamental assumption or guiding belief.
"She refused to cut corners because her core principle is that honesty must always come first in business dealings."
In plain English: A principle is a basic rule or belief that guides how you act or think.
"She refused to compromise on her principle that everyone deserves a fair chance."
Usage: Use "principle" to refer to a fundamental truth, rule, or code of conduct that guides behavior or reasoning. Do not confuse it with "principal," which refers to the head of a school or the main amount in a financial transaction.
To equip with principles; to establish, or fix, in certain principles; to impress with any tenet or rule of conduct.
"The mentor spent months trying to instill a strong work ethic and integrity into the young apprentice until he was fully grounded in those values."
In plain English: To principle as a verb means to make something based on a specific rule or idea.
"The new system will principle itself on user feedback to improve accuracy."
Usage: The word principle is not used as a verb in modern English; it should only be used as a noun meaning a fundamental truth or rule. When you need a verb for this concept, use words like instill, establish, or adhere instead.
The word "principle" comes from Latin, where it originally meant a beginning or foundation. It traveled into English through Old French and Middle English to describe fundamental truths or rules.