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definitions

alter

[awl-ter]
SEE MORE SYNONYMS FOR alter ON THESAURUS.COM

verb (used with object)

to make different in some particular, as size, style, course, or the like; modify: to alter a coat; to alter a will; to alter course.
to castrate or spay.

verb (used without object)

to change; become different or modified.

Origin of alter

1350–1400; Middle English < Old French alterer < Late Latin alterāre to change, worsen, derivative of Latin alter other
Related formsal·ter·er, nounhalf-al·tered, adjectivepre·al·ter, verb (used with object)re·al·ter, verbun·al·ter·ing, adjectivewell-al·tered, adjective
Can be confusedaltar alter

Synonym study

1. See adjust, change.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for alterer

adjective, adverb, conditioner, transformer, alterant
British Dictionary definitions for alterer

alter

verb

to make or become different in some respect; change
(tr) informal, mainly US a euphemistic word for castrate, spay
Derived Formsalterable, adjectivealterably, adverbalterability, noun

Word Origin for alter

C14: from Old French alterer, from Medieval Latin alterāre to change, from Latin alter other
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
Word Origin and History for alterer

alter

v.

late 14c., "to change (something)," from Old French alterer "change, alter," from Medieval Latin alterare "to change," from Latin alter "the other (of the two)," from PIE *al- "beyond" (see alias (adv.)) + comparative suffix -ter (cf. other). Intransitive sense "to become otherwise" first recorded 1580s. Related: Altered; altering.

Online Etymology Dictionary, © 2010 Douglas Harper