En vs. Masse — What's the Difference?

A unit of measurement equal to half an em and approximately the average width of typeset characters, used especially for estimating the total amount of space a text will require.

A stroke in billiards made by striking the cue ball off center with the cue held at a sharper angle than is usual, so that the cue ball moves in a curve before hitting its target ball.

The letter n.

A shot in billiards made by hitting the cue ball with the cue held nearly vertically; the cue ball spins around another ball before hitting the object ball

(Printing) A space equal to half the width of an em.

Abbr of English

(typography) A unit of measurement equal to half an em (half the height of the type in use).

Him

It (when the thing being referred to is masculine)

Half an em, that is, half of the unit of space in measuring printed matter. See Em.

Half the width of an em