A number so large, it can only be described as a 1 followed by an infinite line of zeros. Since it is an infinitely large number, some would argue that it is in fact infinity, but infinity is an abstract concept that cannot be defined as even or odd, while infinitillion is very much even because it can be divided by 2 an infinite amount of times and remain an integer.
You maywish for a gazillion dollars, but I wish for one infinitillion dollars
Enjoyment from infant-related things. Pretending to be a baby, wearing diapers (see diaper lover, speaking like a child (ie "I sowwy"), sleeping in a crib. Wide range of things, but all infant-related
Note that this is interest in the trappings/behaviour of youth, not sexual interest in the youth themselves (that's a pedophile)
Pajama casual is a term used when working from home and preparing for a video conference. All business above the waist and your pajama pants down below.