inch1

[inch] /ɪntʃ/
noun
1.
a unit of length, 1/12 (0.0833) foot, equivalent to 2.54 centimeters.
2.
a very small amount of anything; narrow margin:
to win by an inch; to avert disaster by an inch.
verb (used with object), verb (used without object)
3.
to move by inches or small degrees:
We inched our way along the road.
Idioms
4.
by inches,
  1. narrowly; by a narrow margin:
    escaped by inches.
  2. Also, inch by inch. by small degrees or stages; gradually:
    The miners worked their way through the narrow shaft inch by inch.
5.
every inch, in every respect; completely:
That horse is every inch a thoroughbred.
6.
within an inch of, nearly; close to:
He came within an inch of getting killed in the crash.
Origin
before 1000; Middle English; Old English ynce < Latin uncia twelfth part, inch, ounce. See ounce1
British Dictionary definitions for every inch

inch1

/ɪntʃ/
noun
1.
a unit of length equal to one twelfth of a foot or 0.0254 metre
2.
(meteorol)
  1. an amount of precipitation that would cover a surface with water one inch deep: five inches of rain fell in January
  2. a unit of pressure equal to a mercury column one inch high in a barometer
3.
a very small distance, degree, or amount
4.
every inch, in every way; completely: he was every inch an aristocrat
5.
inch by inch, gradually; little by little
6.
within an inch of, very close to
verb
7.
to move or be moved very slowly or in very small steps: the car inched forward
8.
(transitive) foll by out. to defeat (someone) by a very small margin
Word Origin
Old English ynce, from Latin uncia twelfth part; see ounce1

inch2

/ɪntʃ/
noun
1.
(Scot & Irish) a small island
Word Origin
C15: from Gaelic innis island; compare Welsh ynys
Word Origin and History for every inch

inch

n.

"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).

v.

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

every inch in Science
inch
  (ĭnch)   
A unit of length in the US Customary System equal to 1/12 of a foot (2.54 centimeters). See Table at measurement.
Idioms and Phrases with every inch

every inch

Completely, wholly, as in He was every inch a leader, or I had to argue this case every inch of the way. [ Early 1400s ]