Express

eks-pres': In the King James Version of Heb 1:3 "express" has the meaning "exactly resembling the original," as the impress of a seal resembles the figure engraved upon the seal. Thus "express image" in the verse referred to is a good translation (Greek charakter, literally, "engraving" and hence, "impression"); the Revised Version (British and American) "the very image."

⇒See the definition of express in the KJV Dictionary