| a high, narrow window terminating in a lancet arch. |

| lancet window n. A tall, narrow window set in a lancet arch. |
lancet window
narrow, high window capped by a lancet, or acute, arch. The lancet arch is a variety of pointed arch in which each of the arcs, or curves, of the arch have a radius longer than the width of the arch. It takes its name from being shaped like the tip of a lance. The lancet window is one of the typical features of the Early English (13th century) period in Gothic architecture.
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