The name Quadrant derives from the Latin quadrans, meaning one quarter of a circle. Quadrant Street is recorded by October 1855, when houses there were advertised to let, and nineteenth-century Ordnance Survey mapping shows the street laid out on a regular arc forming part of a circular plan. The name is descriptive of the street’s form and reflects a mid-nineteenth-century practice of geometric street naming in this area, also seen in nearby Albert Crescent, which was established by 1855. The related name Quadrant Road was formally adopted on 4 March 1856, when the Banner of Ulster reported that “the committee have resolved that the road from Durham-street to the Falls-road shall be called ‘Quadrant-road’ in future,” confirming that Quadrant was an established planning term in local use at this time.
Sources:
Northern Whig, 20 October 1855.
Banner of Ulster, 4 March 1856.
Ordnance Survey of Belfast, nineteenth-century editions.