WATCH NOW: How To Know If A Term Is One Word Or Two Words

English loves to take existing words and smash them together so they act as one unit. This is called compounding. But how do you know if a word is one word or two?




Set some time apart to test your bracket symbol knowledge, and see if you can keep your parentheses, squares, curlies, and angles all straight!
Question 1 of 7
Let’s start with some etymology: What are the origins of the typographical word “bracket”?

Origin of compound

First recorded in 1350–1400; (verb) Middle English compounen, from Old French compon- (stem of compondre ), from Latin compōnere, equivalent to com- com- + pōnere “to put”; (adjective) Middle English compouned, past participle of compounen, as above

historical usage of compound

The English verb compound, first appearing in Middle English in the late 14th century as compounen, compownen, comes from Old French compondre, compundre “to direct, arrange,” from Latin compōnere “to put together, add together, match, match up.” The adjective compound, originally a past participle of the verb, is also recorded at the end of the 14th century. The noun, a development of the adjectival sense, is recorded considerably later, in the first half of the 16th century.
The final, unetymological -d in compound arose during the 16th century; it is of the same origin as the -d in the English word sound (meaning “noise”), which developed from the earlier English soun (from Old French son, from Latin sonus ), and the archaic verb round “to whisper,” a derivative of rune “a secret.”


Definition for compound (2 of 2)

[ kom-pound ]
/ ˈkɒm paʊnd /


(in the Far East) an enclosure containing residences, business offices, or other establishments of Europeans.
(in Africa) a similar enclosure for native laborers.
any enclosure, especially for prisoners of war.
any separate cluster of homes, often owned by members of the same family.

Origin of compound

First recorded in 1670–80; alteration, by association with compound1, of Malay kampung “village, collection, gathering”; cf. kampong

historical usage of compound

The noun compound “a large, enclosed area” most likely comes from Malay kampong, kampung “fenced-in space, enclosure, village, a part of town inhabited by a particular nationality.” Compound originally referred to the European (originally Portuguese, Dutch, English) complexes of residences, factories, and warehouses in the East Indies, India, and China. Kampong, kampung was associated in English with the noun compound “something consisting of several parts” by 1679, when the sense “a large, enclosed area” is first recorded.The sense of “large, walled-in space in a prison or other detention camp” first appears in the mid-20th century.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

Example sentences from the Web for compound

British Dictionary definitions for compound (1 of 2)


noun (ˈkɒmpaʊnd)

verb (kəmˈpaʊnd) (mainly tr)

adjective (ˈkɒmpaʊnd)

Derived forms of compound

compoundable, adjectivecompounder, noun

Word Origin for compound

C14: from earlier compounen, from Old French compondre to collect, set in order, from Latin compōnere

British Dictionary definitions for compound (2 of 2)

/ (ˈkɒmpaʊnd) /


(esp formerly in South Africa) an enclosure, esp on the mines, containing the living quarters for Black workers
any similar enclosure, such as a camp for prisoners of war
(formerly in India, China, etc) the enclosure in which a European's house or factory stood

Word Origin for compound

C17: by folk etymology (influenced by compound 1) from Malay kampong village
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

Medical definitions for compound

[ kŏmpound′ ]


A combination of two or more elements or parts.
A pure, macroscopically homogeneous substance that consists of atoms or ions of different elements in definite proportions that cannot be separated by physical means, and that have properties unlike those of its constituent elements.


Consisting of two or more substances, ingredients, elements, or parts.


To combine so as to form a whole; mix.
To produce or create by combining two or more ingredients or parts.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for compound

[ kŏmpound′ ]

A substance consisting of atoms or ions of two or more different elements in definite proportions joined by chemical bonds into a molecule. The elements cannot be separated by physical means. Water, for example, is a compound having two hydrogen atoms and one oxygen atom per molecule.


Composed of more than one part, as a compound eye or leaf.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for compound


In chemistry, a substance containing two or more elements in definite proportions.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Tired of Typos? Get Help Now!