Middle English: from Old French compas (noun), compasser (verb), based on Latin com- ‘together’ + passus ‘a step or pace’. Several senses (‘measure’, ‘artifice’, ‘circumscribed area’, and ‘pair of compasses’) which appeared in Middle English are also found in Old French, but their development and origin are uncertain. The transference of sense to the magnetic compass is held to have occurred in the related Italian word compasso, from the circular shape of the compass box.