boot
     n 1: footwear that covers the whole foot and lower leg
     2: British term for the luggage compartment in a car
     3: the swift release of a store of affective force; "they got a
        great bang out of it"; "what a boot!"; "he got a quick
        rush from injecting heroin"; "he does it for kicks" [syn:
        {bang}, {charge}, {rush}, {flush}, {thrill}, {kick}]
     4: protective casing for something that resembles a leg
     5: an instrument of torture that is used to crush the foot and
        leg [syn: {iron boot}, {iron heel}]
     6: the act of delivering a blow with the foot; "he gave the
        ball a powerful kick"; "the team's kicking was excellent"
        [syn: {kick}, {kicking}]
     v 1: kick; give a boot to
     2: cause to load (an operating system) and start the initial
        processes; "boot your computer" [syn: {reboot}, {bring up}]
Source: WordNet® 2.0

boot v.,n. [techspeak; from `by one's bootstraps'] To load and
   initialize the operating system on a machine. This usage is no longer
   jargon (having passed into techspeak) but has given rise to some
   derivatives that are still jargon.

   The derivative `reboot' implies that the machine hasn't been down for
   long, or that the boot is a {bounce} (sense 4) intended to clear some
   state of {wedgitude}. This is sometimes used of human thought processes,
   as in the following exchange: "You've lost me." "OK, reboot. Here's the
   theory...."

   This term is also found in the variants `cold boot' (from power-off
   condition) and `warm boot' (with the CPU and all devices already powered
   up, as after a hardware reset or software crash).

   Another variant: `soft boot', reinitialization of only part of a
   system, under control of other software still running: "If you're
   running the {mess-dos} emulator, control-alt-insert will cause a
   soft-boot of the emulator, while leaving the rest of the system
   running."

   Opposed to this there is `hard boot', which connotes hostility towards
   or frustration with the machine being booted: "I'll have to hard-boot
   this losing Sun." "I recommend booting it hard." One often hard-boots by
   performing a {power cycle}.

   Historical note: this term derives from `bootstrap loader', a short
   program that was read in from cards or paper tape, or toggled in from
   the front panel switches. This program was always very short (great
   efforts were expended on making it short in order to minimize the labor
   and chance of error involved in toggling it in), but was just smart
   enough to read in a slightly more complex program (usually from a card
   or paper tape reader), to which it handed control; this program in turn
   was smart enough to read the application or operating system from a
   magnetic tape drive or disk drive. Thus, in successive steps, the
   computer `pulled itself up by its bootstraps' to a useful operating
   state. Nowadays the bootstrap is usually found in ROM or EPROM, and
   reads the first stage in from a fixed location on the disk, called the
   `boot block'. When this program gains control, it is powerful enough to
   load the actual OS and hand control over to it.


Source: The Jargon File