steadfast (adj.)

Old English stede "place, position; standing, firmness, stability, fixity," from Proto-Germanic *stadi- (source also of Old Saxon stedi, Old Norse staðr "place, spot; stop, pause; town," Swedish stad, Dutch stede "place," Old High German stat, German Stadt "town," Gothic staþs "place"), from PIE *steti-, suffixed form of root *sta- "to stand, make or be firm." Related to stand.

Now chiefly in compounds or phrases. Meaning "assistance, use, benefit, advantage" is from c. 1300. Meaning "frame on which a bed is laid" is from c. 1400. The German use of Stadt for "town, city" "is a late development from c. 1200 when the term began to replace Burg" [Cambridge Dictionary of English Place-Names]. The Steads was 16c. English for "the Hanseatic cities."

Old English fæst "firmly fixed, steadfast, constant; secure; enclosed, watertight; strong, fortified," probably from Proto-Germanic *fastu- "firm, fast" (source also of Old Frisian fest, Old Norse fastr, Dutch vast, German fest), from PIE root *past- "firm, solid" (source of Sanskrit pastyam "dwelling place").

Meaning "rapid, quick" is from 1550s, from fast (adv.) , in which entry the attempt is made to explain how a root meaning "firm, solid" came variously to yield words for "refrain from eating" (fast (v.)) and "rapid, quick." Of colors, from 1650s; of clocks, from 1840. The sense of "living an unrestrained life, eager in pursuit of pleasure" (usually of women) is from 1746 (fast living is from 1745).

Fast buck recorded from 1947; fast food is first attested 1951. Fast lane is by 1966; the fast track originally was in horse-racing (1934), one that permits maximum speed; figurative sense by 1960s. Fast-forward is by 1948, originally of audio tape.