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Synonyms

oak

American  
[ohk] / oʊk /

noun

  1. any tree or shrub belonging to the genus Quercus, of the beech family, bearing the acorn as fruit.

  2. the hard, durable wood of an oak tree, used in making furniture and in construction.

  3. Archaic. the leaves of an oak tree, especially as worn in a chaplet.


adjective

  1. pertaining to or made of oak.

    an antique oak desk;

    heavy oak doors with double locks.

idioms

  1. sport one's oak, (of a university student) to indicate that one is not at home to visitors by closing the outer door of one's lodgings.

oak British  
/ əʊk /

noun

  1. any deciduous or evergreen tree or shrub of the fagaceous genus Quercus, having acorns as fruits and lobed leaves See also holm oak cork oak red oak Turkey oak durmast

    1. the wood of any of these trees, used esp as building timber and for making furniture

    2. ( as modifier )

      an oak table

  2. any of various trees that resemble the oak, such as the poison oak, silky oak, and Jerusalem oak

    1. anything made of oak, esp a heavy outer door to a set of rooms in an Oxford or Cambridge college

    2. to shut this door as a sign one does not want visitors

  3. the leaves of an oak tree, worn as a garland

  4. the dark brownish colour of oak wood

  5. any of various species of casuarina, such as desert oak, swamp oak, or she-oak

"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

  • oaklike adjective

Etymology

Origin of oak

First recorded before 900; Middle English ok(e), oc, Old English āc; cognate with Dutch eik, German Eiche, Old Icelandic eik; further origin uncertain

Explanation

An oak is a tree that typically sheds its leaves in the winter and grows acorns as fruit. If you get hit on the head with an acorn, you are probably standing under an oak. There are many species of oaks, a few of which are evergreen, keeping their leaves all year, but most have bright leaves in the fall and are bare for the winter months. An oak table or oak desk is made from the sturdy wood of an oak tree. The strength of oaks has inspired several countries to adopt them as symbols on money and flags, and in 2004 the oak was voted the national tree by the US Congress.

Keep Reading on Vocabulary.com

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.

His only cosmetic update was painting over the original oak stain on the vanity about 15 years ago.

From The Wall Street Journal • Apr. 8, 2026

At more than 4,000 feet, up in the Cuyamaca Mountains, it rests among coastal live oak woodlands and Coulter pine forests.

From Los Angeles Times • Apr. 7, 2026

Options already exist for fixing dyes without lead, including natural mordants derived from plants rich in tannins, such as oak bark, pomegranate peel and rosemary, as well as alum, which is considered environmentally safe.

From Science Daily • Apr. 2, 2026

He calls it an “ultimate expression” that balances an “aged oak influence with fresh fruit notes.”

From MarketWatch • Mar. 10, 2026

In the next picture the oak tree outside my aunt’s boardinghouse is captured, in grease pencil, at change of season, the leaves all reds and golds.

From "The Brightwood Code" by Monica Hesse