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Synonyms

oily

American  
[oi-lee] / ˈɔɪ li /

adjective

oilier, oiliest

  1. smeared or covered with oil; greasy.

    an oily road surface.

  2. of the nature of, consisting of, or resembling oil.

  3. of or relating to oil.

  4. full of or containing oil.

  5. smooth or unctuous, as in manner or speech.

    an oily hypocrite.
    Synonyms:
    smarmy

adverb

  1. in an oily manner.

oily British  
/ ˈɔɪlɪ /

adjective

  1. soaked in or smeared with oil or grease

  2. consisting of, containing, or resembling oil

  3. flatteringly servile or obsequious

"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

Other Word Forms

Etymology

Origin of oily

First recorded in 1520–30; oil + -y 1

Explanation

Oily things are greasy, slippery, or covered with oil — think a bowl of oily pasta or the oily garage floor after you've been tinkering with your motorcycle's engine. Anything containing oil, covered in oil, or resembling oil is oily. A batch of muffins might taste weirdly oily when you use too much butter, and the rags lying around a car repair shop are mostly black and oily. Your brother's hair will probably be pretty oily after he refuses to wash it for a month. Since the sixteenth century, oily has also had the figurative meaning of "insincerely flattering or slick," like an oily car salesman.

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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.

Oily fish has been part of many countries' cultural heritage throughout history.

From Salon • Apr. 23, 2024

Oily surfaces also change the way water ripples when it is windy, making oil-covered patches of the ocean’s surface look calmer and smoother than surrounding areas.

From Scientific American • Jun. 16, 2022

Oily hands and pan aside, I was surprised to conclude that focaccia was easier to master than a lot of yeast loaves, less fussy and less prone to errors.

From Seattle Times • Oct. 5, 2021

Oily Cart understands this, which is why they keep “In a Pickle” friendly, focused and fast-moving.

From New York Times • Apr. 24, 2017

Oily black scales bristling with barbed spikes covered its grotesque body.

From "Fablehaven" by Brandon Mull

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.