[reg-yuh-luh] 
[-lee] . | (in a Doric entablature) a fillet, continuing a triglyph beneath the taenia, from which guttae are suspended. |
regula
(from Latin filum, "thread"), in architecture, the characteristically rectangular or square ribbonlike bands that separate moldings and ornaments. Fillets are common in classical architecture (in which they also may be found between the flutings of columns) and in Gothic architecture. In the Early English and Decorated styles of the 13th and 14th centuries, respectively, the fillet is frequently worked upon larger moldings and column shafts; in these cases it is not always flat but rather is sometimes cut into two or more narrow faces that have sharp edges between them. See also molding
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