Green’s Dictionary of Slang

to toady, to ingratiate, thus ext. smarm it up; to speak or behave smugly.

1936		J. Curtis Gilt Kid 258: If they thought they’d get him by smarming they got another coming.
1941		G.D.H. & M. Cole Counter-point Murder 11: It’s no good thinking you can smarm your way out of it.
1950		C. Harris Three-Ha’Pence to the Angel 189: I could a wiped ’im round the jaw, any of ’em, come smarming up ter me.
1954		J. Phelan Tramp at Anchor 57: Some were obvious petty snobs, fawning and smarming round the higher officials.
1960		J. Iggulden Storms of Summer 29: You ever meet any of these soppy bastards . . . you know? [...] Smarming around like tuppenny ha’penny Jesus Christs?
1989		H. Rawson Dict. of Invective (1991) 361: The verb, to smarm, i.e., to flatter or toady (up to).
1994		C. McCullough Fortune’s Favorites 336: How he plotted and schemed to cover his tracks, how he smarmed and greased in the presence of his patron.
1999		Sydney Morn. Herald 6 Sept. n.p.: Weaving [...] has been smarming it up in cinemas recently.
2003		D. Duncan Paragon Lost 55: Then he fawned, smarmed, toadied, and truckled. ‘Your Majesty’s presence will lift all hearts.’ Yuck.
2015		‘Elvis Costello’ Unfaithful Music 255: A senior BBC music programmer smarmed up to me and took this opportunity to remind me of my diminished status .
2024		J. Meades Empty Wigs (t/s) 811: [T]hey don’t look down their noses at a Cordoba Vitesse at the [...] Golf and Country Club where he smarmed for work.