In classical architecture, the lowest division of an entablature, the epistyle (a stone beam). In the case of a square opening it may be any moulded or similarly ornamented band framing a square window or door, or projecting irom it.
A banded architrave is one spaced at intervals by projecting blocks.
A jack architrave is, in certain orders, the lowest fascia (band or strip) of the architrave proper.
Architrave trim is a casing carried around the sides and ‘top of an opening; it resembles an architrave.