agate

[ ag-it ]
/ ˈæg ɪt /

noun

a variegated chalcedony showing curved, colored bands or other markings.
a playing marble made of this substance, or of glass in imitation of it.
Printing. a 5½-point type of a size between pearl and nonpareil.Compare ruby(def 6).

Origin of agate

1150–1200; Middle English ac(c)ate, achate, agaten (compare Dutch agaat, Old Saxon agāt, Old High German agat), apparently < Old French agathe or Italian agata (initial stress) ≪ Medieval Latin achātēs < Greek achā́tēs

Related forms

ag·ate·like, ag·a·toid, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for agatoid (1 of 3)

agate

1
/ (ˈæɡɪt) /

noun

an impure microcrystalline form of quartz consisting of a variegated, usually banded chalcedony, used as a gemstone and in making pestles and mortars, burnishers, and polishers. Formula: SiO 2
a playing marble of this quartz or resembling it
Also called: ruby printing, US and Canadian (formerly) a size of printer's type approximately equal to 5 1/2 point

Word Origin for agate

C16: via French from Latin achātēs, from Greek akhatēs

British Dictionary definitions for agatoid (2 of 3)

agate

2
/ (əˈɡeɪt) /

adverb

Northern English dialect on the way

Word Origin for agate

C16: a-² + gate³

British Dictionary definitions for agatoid (3 of 3)

Agate

/ (ˈæɡeɪt) /

noun

James (Evershed). 1877–1947, British theatre critic; drama critic for The Sunday Times (1923–47) and author of a nine-volume diary Ego (1935–49)

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

Science definitions for agatoid

agate

[ ăgĭt ]

A type of very fine-grained quartz found in various colors that are arranged in bands or in cloudy patterns. The bands form when water rich with silica enters empty spaces in rock, after which the silica comes out of solution and forms crystals, gradually filling the spaces from the outside inward. The different colors are the result of various impurities in the water.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.