A person with no significant value what so ever. This person has hardly any association to you. This person is most likely also a major douche.
"I can't believe you got into a fight with me cause of that unsignificunt." "I'm youboyfriend and he's a friend that you hardly even talk to." Therefor that "friend" is a unsignificunt.
The word size on a computer. Basically the size of the largest number that can be added/subtracted at one time on a processor. In the x86-64, however, an int stayed the same size as in the x86.
x86 has a wordsize of 32, and x86-64 has unsigned ints with a size of 32 (wtf?)