טֹפַחṭôphach

span, hand-breadth, always absolute טֹפַח (Ezekiel 40:43; Exodus 25:25; Exodus 37:12; Ezekiel 40:5; Ezekiel 43:13)

Pronunciation: to'-fakh · Hebrew/Aramaic (Old Testament) · H2948

Same root

טָפַחṭâphach · H2946to flatten out or extend (as a tent); figuratively, to nurse achild (as promotive of growth);
טֵפַחṭêphach · H2947a spread of the hand, i.e. a palm-breadth (not 'span' of the fingers); architecturally, a corbel (as a supporting palm)

Where it appears

Appears 5 times in the Bible.

Exodus 25:25 Decorate it with a 3-inch border all around, and run a gold molding along the border.
Exodus 37:12 He decorated it with a 3-inch border all around, and he ran a gold molding along the border.
Ezekiel 40:5 I could see a wall completely surrounding the Temple area. The man took a measuring rod that was 10 1⁄2 feet long and measured the wall, and the wall was 10 1⁄2 feet thick and 10 1⁄2 feet high.
Ezekiel 40:43 There were hooks, each 3 inches long, fastened all around the foyer walls. The sacrificial meat was laid on the tables.
Ezekiel 43:13 “These are the measurements of the altar: There is a gutter all around the altar 21 inches deep and 21 inches wide, with a curb 9 inches wide around its edge. And this is the height of the altar:

Source: Brown, Driver and Briggs, Hebrew and English Lexicon of the Old Testament (1906), public domain; markup by unfoldingWord, CC BY (github.com/unfoldingWord/Brown-Driver-Briggs-Enhanced).