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Synonyms

unprincipled

American  
[uhn-prin-suh-puhld] / ʌnˈprɪn sə pəld /

adjective

  1. lacking or not based on moral scruples or principles.

    an unprincipled person; unprincipled behavior.

    Synonyms:
    dishonest, tricky
  2. not instructed in the principles of something (usually followed byin ).


unprincipled British  
/ ʌnˈprɪnsɪpəld /

adjective

  1. lacking moral principles; unscrupulous

  2. archaic (foll by in) not versed in the principles of (a subject)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Related Words

See unscrupulous.

Other Word Forms

Etymology

Origin of unprincipled

First recorded in 1625–35; un- 1 + principled

Explanation

An unprincipled person follows no moral code, has no integrity, and should not be trusted, like the guy who offers to help an old lady across the street but steals her purse instead. No, unprincipled isn't a word we use to describe a school that's missing its principal — we're talking about the -ple word here. If you don't have principles, which is what unprincipled really means, then you don't have scruples or morals. You're likely to do just about anything bad, like break rules, take advantage of people, tell lots of lies, and extort people's lunch money.

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Vocabulary lists containing unprincipled

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Unprincipled athletes cheat or change the rules in order to win.

From The Guardian • Apr. 6, 2019

Robin Williams is a Peter Unprincipled, grounded in all the latest guilts and anxieties.

From Time Magazine Archive

Bush's first attack ad, run on the Web, was titled "Unprincipled."

From Time Magazine Archive

Unprincipled or incompetent examiners are to blame for some of these problems, and in fact the uneven quality of the operators is an admitted industry problem.

From Time Magazine Archive

Unprincipled as she was, she did not abandon herself to utter selfishness.

From Notable Women of Olden Time by Anonymous