mariner's compass

noun
  1. a compass used for navigational purposes, consisting of a pivoted compass card in a gimbal-mounted, nonferrous metal bowl.
  2. (initial capital letter) Astronomy. compass(def 8a).

Origin of mariner's compass

First recorded in 1620–30
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018