Pissant: one that is insignificant. Of course I use it all the time, but no one else does.
Insufferable: not to be endured, intolerable (“an insufferable bore”)
Whenever anyone complains I like to comment on their insufferable suffering. Very occasionally someone realizes I’m not empathizing with them. 
copious Lots and lots and lots.
Gob Smacked - Shocked and left slack jawed
Gob shite - someone who will not shut up or who speaks rubbuish!
To Gob ( Verb) - to spit, usualy with a loud and vocalised noise from the back of the throat
Wing Nut - for a person with prominant ears
Clarty Midden - term of endearmeny ( ironic ) or insult depending on how it is used
Supercalifragilisticexpialidocious - just cos I can say it!
Mirabilis Jalapa - cos I like the flower
Oh and fortnight is in daily use on this side of the pond - that is the Eastern Side where the sun comes up earlier!
and defenstration is to throew yourself or an object out of the window… you would have a real problem eexfenestrating yourself.
Hmmm…I don’t think I know anyone who doesn’t know the meaning of the word “fortnight.” That is the type of word that shows up on middle school spelling/definition tests. <shrugs>
That reminds me of a favorite bit of dialogue from a David Eddings book. Two characters are talking about what the woman (an amazon type) did to someone who was making unwanted advances:
IICR
“…then I defenstrated him.”
" That’s a horrible thing to do to a man!"
" I mean I threw him out the window."
" Oh. Well that’s all right then."
debacle- voting in florida
avitar- yeah, thats me!
gormandize- damn, I was hungry!
I’m not nearly as stupid as I think I am.
Recapitulate. (“Recap” is the often-used abbreviation.)
As an example, an instructor could say, “Let’s recapitulate what we learned yesterday.”
discomknockerate
Thought a few regional dialectic bits might help!