clerical collar

noun
1.
a stiff, narrow, bandlike white collar fastened at the back of the neck, worn by certain clerics.
Also called reversed collar, Roman collar.
Origin
1945-50
British Dictionary definitions for clerical collar

clerical collar

noun
1.
a stiff white collar with no opening at the front that buttons at the back of the neck; the distinctive mark of the clergy in certain Churches Informal name dog collar