Doublet

From BelegarthWiki

Doublets are a type of close-fitting jacket. They were popular from the late 14th century to during the Renaissance. They may or may not have sleeves, which could be laced on and detachable, or fixed to the garment and the point where the sleeve joined the torso was smaller than modern garments.

Doublets are relatively simple to sew and are often used as feast garb.