In ordinary usage, coat
(kǔttō’něṯ) is a Hebrew word that refers to an everyday article of clothing worn by men and women alike. However, when spoken of in the context of the priesthood, the coat describes a long undergarment made of fine linen that was worn as a first layer (Exodus 28:39).
7 And he put the coat on him and tied the sash around his waist and clothed him with the robe and put the ephod on him and tied the skillfully woven band of the ephod around him, binding it to him with the band.