a unit of length, 1/12 (0.0833) foot, equivalent to 2.54 centimeters.
a very small amount of anything; narrow margin: to win by an inch; to avert disaster by an inch.

verb (used with or without object)

to move by inches or small degrees: We inched our way along the road.


    by inches,
    1. narrowly; by a narrow margin: escaped by inches.
    2. Also inch by small degrees or stages; gradually: The miners worked their way through the narrow shaft inch by inch.
    every inch, in every respect; completely: That horse is every inch a thoroughbred.
    within an inch of, nearly; close to: He came within an inch of getting killed in the crash.

Origin of inch

before 1000; Middle English; Old English ynce < Latin uncia twelfth part, inch, ounce. See ounce1 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for inch by inch




a unit of length equal to one twelfth of a foot or 0.0254 metre
  1. an amount of precipitation that would cover a surface with water one inch deepfive inches of rain fell in January
  2. a unit of pressure equal to a mercury column one inch high in a barometer
a very small distance, degree, or amount
every inch in every way; completelyhe was every inch an aristocrat
inch by inch gradually; little by little
within an inch of very close to


to move or be moved very slowly or in very small stepsthe car inched forward
(tr foll by out) to defeat (someone) by a very small margin

Word Origin for inch

Old English ynce, from Latin uncia twelfth part; see ounce 1




Scot and Irish a small island

Word Origin for inch

C15: from Gaelic innis island; compare Welsh ynys
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 inch by inch



"move little by little," 1590s, from inch (n.1). Related: Inched; inching.



"linear measure, one-twelfth of a foot," late Old English ynce, Middle English unche (current spelling c.1300), from Latin uncia "a twelfth part," from root of unus "one" (see one). An early borrowing from Latin, not found in any other Germanic language. Transferred and figurative sense of "a very small amount" is attested from mid-14c. For phrase give him an inch ... see ell.



"small Scottish island," early 15c., from Gaelic innis (genitive innse) "island, land by a river," from Celtic *inissi (cf. Old Irish inis, Welsh ynys, Breton enez).

Online Etymology Dictionary, © 2010 Douglas Harper

Science definitions for inch by inch



A unit of length in the US Customary System equal to 112 of a foot (2.54 centimeters). See Table at measurement.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Idioms and Phrases with inch by inch

inch by inch

see by inches.


In addition to the idioms beginning with inch

  • inch along
  • inch by inch

also see:

  • by inches
  • every inch
  • give an inch
  • within an ace (inch) of
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.