lancet
n. countable C2 Proficiency US //ˈɫænsət// UK //lˈɑːnsɪt// lancet
n. a small, very sharp knife with two edges. Doctors use it to make small cuts or to take blood samples.
n. a small, broad, two-edged surgical knife with a sharp point. Also refers to a high, narrow window with a pointed arch in Gothic architecture.
The doctor used a sterile lancet to prick my finger.
The surgeon carefully selected a lancet to perform the delicate incision required for the procedure.
The cathedral's facade was dominated by tall lancet windows that allowed narrow shafts of light to illuminate the stone floor of the nave.
From Middle English launcet, from Old French lancete, a diminutive of lance. By surface analysis, lance + -et.
Usage
In its architectural sense, it often appears as a modifier in the phrase 'lancet window'.