(あつ)

あつさ
noun
thickness
See also: (あつ) (heat (weather))
1. thickness
The distance between two opposite surfaces of something.
The thickness of this book is 3 centimeters.
(かべ)(あつ)(はか)
To measure the thickness of the wall.
(あつ)さ5ミリ(いた)
A board 5 millimeters thick

(あつ)さ is a measurement noun derived from the adjective (あつ) (thick) + the nominalizing suffix さ. It expresses thickness as a measurable quantity.

Common patterns

Watch out

Do not confuse with (あつ) (heat/hotness from weather), which has the same reading but different kanji and meaning.

Related measurement nouns

All follow the same い-adjective stem + さ pattern to create nouns expressing degree or measurement.