boot¹ / boōt/ • n. 1. a sturdy item of footwear covering the foot, the ankle, and sometimes the leg below the knee: walking boots. ∎ a covering or sheath to protect a mechanical connection, as on a gearshift. ∎  (also Denver boot) a clamp placed by the police on the wheel of an illegally parked vehicle to make it immobile.2. inf. a hard kick: I got a boot in the stomach.3. Brit. the trunk of a car.4. (also boot up) [usu. as adj.] the process of starting a computer and putting it into a state of readiness for operation: a boot disk.5. Mil. a navy or marine recruit.• v. [tr.] 1. [usu. as adj.] (booted) place boots on (oneself, another person, or an animal): thin, booted legs. 2. [tr.] kick (something) hard in a specified direction: he ended up booting the ball into the stands. ∎  (in an athletic contest) misplay (a ball); mishandle (a play). ∎  (boot someone out) inf. force someone to leave a place, institution, or job unceremoniously: she had been booted out of school.3. start (a computer) and put it into a state of readiness for operation: the menu will be ready as soon as you boot up your computer [intr.] the system won't boot from the original drive. PHRASES: get the boot inf. be dismissed from one's job.give someone the boot inf. dismiss someone from their job.boot² • n. (in phrase to boot) as well; in addition: images that are precise, revealing, and often beautiful to boot.

boot a boot is the emblem of the English priest John Schorne (d. c.1315), centre of a popular cult, who was said to have trapped the Devil in his boot.
boot and saddle a cavalry signal to mount, from an alteration of French boute-selle ‘place-saddle’.
by one's own bootstraps by one's own efforts. A bootstrap was sewn into boots to help with pulling them on. The idiom has given rise to the term bootstrapping, meaning to ‘make use of existing resources to improve one's position’, hence the computer term booting.

See also a lie is halfway round the world before the truth has got its boots on at lie1, seven-league boots.

boot1 (arch.) advantage (in phr. to boot †to advantage, in addition); †making good, remedy. OE. bōt = OS. bōta OHG. buoʒa (G. busse), ON. bót, Goth. bōta :- Gmc. *bōtō, f. *bōt- *bat- (see BETTER, BEST).
Hence boot vb. profit, avail. XIV. bootless irremediable (OE. bōtlēas); useless XVI.

boot2
A. covering for the foot and (lower part of) the leg XIV;

B. †space for attendants on the outside of a coach XVII; receptacle for luggage on a coach XVIII. ME. bote — ON. boti or its source, OF. bote (mod. botte); in AL. bota (XII), botta; of unkn. orig. The senses under B appear to derive from modF.

boot To start a computer by turning the power on. Specifically, to invoke a bootstrap, especially to read from backing store the operating system of a computer and load it into the empty memory.