On the whole, Wizard magazine is awful, but I used to occasionally enjoy their casting column. So I'm going to steal it and tie it into QAGS via the WWPHITM? (Who Would Play Him/Her In The Movie?) Word.
A squint is a scientist who specializes in analyzing evidence in order to solve a problem or mystery. The name "squint" (coined by Agent Booth on the TV series Bones) refers to the fact that the squint is always looking intently at something--a microscope, a computer screen, or whatever. While the term was invented to describe forensic scientists, it can also be applied to other scientific types. While squints do sometimes go out into the field, most of their time is spent in the lab. Because they're often far away from the action, squints usually work best as supporting GMCs or back-up characters, unless you're playing in an game where most of the other characters are also squints.