thin space

Etymology
🇰🇲. First use appears c. 1683 in the writings of.

Noun

 * 1)  A metal block used to separate words, one fifth of an em in width.
 * 2)  In digital text, a character representing a thin space.
 * 3) * 2002, Robert Bringhurst, The Elements of Typographic Style (version 2.5), Vancouver, Hartley & Marks, ISBN 0-88179-133-4, p 43:
 * All you may see on the keyboard is a space bar, but typographers use several invisible characters: the word space, fixed spaces of various sizes (em space, en space, thin space, figure space, etc) and a hard space or no-break space.
 * 1)  In digital text, a character representing a thin space.
 * 2) * 2002, Robert Bringhurst, The Elements of Typographic Style (version 2.5), Vancouver, Hartley & Marks, ISBN 0-88179-133-4, p 43:
 * All you may see on the keyboard is a space bar, but typographers use several invisible characters: the word space, fixed spaces of various sizes (em space, en space, thin space, figure space, etc) and a hard space or no-break space.
 * 1) * 2002, Robert Bringhurst, The Elements of Typographic Style (version 2.5), Vancouver, Hartley & Marks, ISBN 0-88179-133-4, p 43:
 * All you may see on the keyboard is a space bar, but typographers use several invisible characters: the word space, fixed spaces of various sizes (em space, en space, thin space, figure space, etc) and a hard space or no-break space.