"pertaining to the system of weights and measures based on the meter," 1855, from French métrique, from mèter (see meter (n.2)). In this sense, metrical is attested from 1797. Metric system is attested by 1855.
The noun meaning "premature ignition in an internal-combustion engine" is recorded by 1897. As a verb, of schemes, plans, etc., "to affect the initiator rather than the intended object" it is attested from 1912, a figurative use from the accidental back-firing of firearms.
1975, transitive, "start up (a computer) by causing an operating system to load in the memory," from bootstrap (v.), a 1958 derived verb from bootstrap (n.) in the sense of "fixed sequence of instructions to load the operating system of a computer" (1953).
This is from the notion of the first-loaded program pulling itself (and the rest) up by the bootstrap. The intransitive use, of a computer operating system, is from 1983. Related: Booted; booting.
former transliteration of the name of the Chinese capital city, now (in the pinyin system) called Beijing. In the Wade-Giles system it was Peiping; the form Peking pre-dates Wade-Giles and was formed by the old British-run, Hong Kong-based Chinese postal system. Peking duck, "large domestic duck of white plumage and orange beak and legs," is attested from 1880.