geezer and twit

The OED tells us that geezer is a dialectical pronunciation of guiser "one who guises, a masquerader, a mummer".

1893 R. O. Heslop Northumberland Words, Geezer, a mummer; and hence any grotesque or queer character.

guise "to go about in disguise, or masquerade dress" was derived from the noun guise "manner, method, way, fashion, style", borrowed from Old French guise, which was borrowed from Proto-Germanic *wīsōn- "appearance, form, manner" from Proto-Indo-European *weid- "to see" (AHD).

Old French guise plus the des-/de- prefix became desguisier, borrowed into English as disgisen/disguise "to alter the guise or fashion of dress and appearance" (OED).

*weid- became Old English wītan "to blame, reproach". This plus the prefix æt- became atwite "to cast an imputation upon, reproach". This became twite thru aphesis, then twit "a (light) censure or reproach; a taunt; a fool; a stupid or ineffectual person" (OED).