subs. (old).The state barge, used by the Lord Mayor when he was sworn in at Westminster.
1609. JONSON, Epicœne, or the Silent Woman, iv., 2. Out of my doores, you sons of noise and tumult, begot on an ill May day, or when the GALLEYFOIST is afloate to Westminster.
1785. GROSE, A Classical Dictionary of the Vulgar Tongue, s.v.
1811. GROSE and CLARKE, Lexicon Balatronicum, s.v.