b. In fact; in reality
c. the act of agreeing.
d. simulaneously concurring while being a smart arse
used in place of the word "indeed".
Since its creation in 2008, invented by the most wonderful person in the world, the "ium" fad has emerged.
PersonB: "indeedium, it's that gigantic that in the morning when i crack a wood.. i dont just pitch a tent, i thrust a hole straight through the roof"
PersonA: "i see, well that would explain why your house has 12 sky-lights and 15 fire places"