micro- pref.
1. Very small; this is the root of its use as a quantifier
prefix. 2. A quantifier prefix, calling for multiplication by
10^(-6) (see quantifiers).
Neither of these uses is peculiar to hackers, but hackers tend to
fling them both around rather more freely than is countenanced in
standard English. It is recorded, for example, that one CS
professor used to characterize the standard length of his
lectures as a microcentury -- that is, about 52.6 minutes (see
also attoparsec, nanoacre, and especially microfortnight). 3. Personal or
human-scale -- that is, capable of being maintained or
comprehended or manipulated by one human being. This sense is
generalized from `microcomputer', and is esp. used in contrast
with `macro-' (the corresponding Greek prefix meaning `large').
4. Local as opposed to global (or macro-). Thus a hacker might say that buying a
smaller car to reduce pollution only solves a microproblem; the
macroproblem of getting to work might be better solved by using
mass transit, moving to within walking distance, or (best of all)
telecommuting.