Glossary
try square
A try square is an L-shaped tool with a thick stock and a thin steel blade set at exactly 90 degrees. It marks and checks square corners and straight edges.
A try square is an L-shaped layout tool: a thick handle called the stock and a thin steel blade fixed at exactly 90 degrees to it. It is used to mark square lines across a board and to check that a corner or an end is truly square.
To use it, press the stock firmly against a known straight edge and mark or sight along the blade, which becomes your square line. Pressing the stock against a crooked edge produces a crooked line, so which face you trust is a real decision. It checks as well as marks: hold the stock against one face and bring the blade across the end, and any sliver of daylight under the blade shows the cut is out of square.
It is a marking and checking tool, never a striking tool or a pry bar. A square that has been dropped is no longer square, which is why a try square is commonly compared with a combination square.
Taught in
Related terms
- plumb bob — A plumb bob is a pointed weight hung on a cord. Gravity pulls the cord straight down, and the line it makes — a plumb line — is used to check that something is vertical.
Source: Official ASVAB — subtest descriptions (what each subtest asks) and the CAT-ASVAB scored-question counts (accessed 2026-09)