Webster's Revised Unabridged Dictionary · 1913

Inch

Inch (inch) , noun

[Gael. inis.]

An island; -- often used in the names of small islands off the coast of Scotland, as in Inchcolm, Inchkeith, etc. [Scottish]

Inch , noun

[Old English inche, unche, Anglo-Saxon ynce, Latin uncia the twelfth part, inch, ounce. See Ounce a weight.]

1.
A measure of length, the twelfth part of a foot, commonly subdivided into halves, quarters, eights, sixteenths, etc., as among mechanics. It was also formerly divided into twelve parts, called lines, and originally into three parts, called barleycorns, its length supposed to have been determined from three grains of barley placed end to end lengthwise. It is also sometimes called a prime (′), composed of twelve seconds (′′), as in the duodecimal system of arithmetic.
12 seconds (′′) make 1 inch or prime. 12 inches or primes (′) make 1 foot. — B. Greenleaf

The symbol ′ is the same symbol as the light accent, or the "minutes" of an arc. The "seconds" symbol should actually have the two strokes closer than in repeated "minutes", but in this dictionary ′′ will be interpreted as "seconds".

The meter, the accepted scientific standard of length, equals 39.37 inches; the inch is equal to 2.54 centimeters. See Metric system, and Meter.

2.
A small distance or degree, whether of time or space; hence, a critical moment; also used metaphorically of minor concessions in bargaining; as, he won't give an inch; give him an inch and he'll take a mile.
Beldame, I think we watched you at an inch. — Shakespeare
Collocations (5)
By inches , by slow degrees, gradually.
Inch of candle , See under Candle.
Inches of pressure , usually, the pressure indicated by so many inches of a mercury column, as on a steam gauge.
Inch of water , See under Water.
Miner's inch (Hydraulic Mining) , a unit for the measurement of water. See Inch of water, under Water.

Inch , transitive verb

1.
To drive by inches, or small degrees. [Rare]
He gets too far into the soldier's grace And inches out my master. — Dryden
2.
To deal out by inches; to give sparingly. [Rare]

Inch , intransitive verb

To advance or retire by inches or small degrees; to move slowly; as, to inch forward.
With slow paces measures back the field, And inches to the walls. — Dryden

Inch , adjective

Measuring an inch in any dimension, whether length, breadth, or thickness; -- used in composition; as, a two-inch cable; a four-inch plank.
Collocations (1)
Inch stuff , boards, etc., sawed one inch thick.