porpus, n. — Green’s Dictionary of Slang

porpus n.

[? joc. use of SE porpoise, i.e. an odd fish under odd adj.]

(UK Und.) a stupid pompous fellow.

1747		Life and Character of Moll King 12: We had ne’er a Queer Cull, a Buttock, or a Porpus, amongst them, but all as Rum and as Quiddish as ever Jonathan sent to be great Merchants in Virginia.
1757		Smollett Reprisal II xiv: Peace, porpuss.
[1851		R.S. Surtees Young Tom Hall (1926) 23: A great porpoise of a boy in all the coloures of the rainbow hanging about the streets].
1884		Ally Sloper’s Half Holiday 3 May 3/3: Some of the ladies do not hesitate to call him behind his back ‘pig’ and ‘porpoise’.