A person who measures or works with callipers; someone who uses callipers as part of their job.
From calliper + -er (one who does). Uncommon term, formed by regular English word formation rules to denote a person whose task involves measuring with callipers.
Calliperer is such a beautifully specific job title that it's rarely used—it describes someone whose entire responsibility is precise measurement, which in our world usually means they're hidden inside a larger profession.
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