calliper

Universal Words noun (BrE) (also caliper AmE, BrE) 1 (callipers) [pl.] an instrument with two long thin parts joined at one end, used for measuring the DIAMETER of tubes and round objects (= the distance across them): a pair of callipers 2 (BrE) (AmE brace) [C,usually pl.] a metal support for weak or injured legs