tune-up n.

"bring into a state of proper pitch," c. 1500, from tune (n.). Non-musical meaning "to adjust an organ or receiver, put into a state proper for some purpose" is recorded from 1887. Verbal phrase tune in in reference to radio (later also TV) is recorded from 1913; figurative sense of "become aware" is recorded from 1926. Tune out "eliminate radio reception" is recorded from 1908; figurative sense of "disregard, stop heeding" is from 1928. Related: Tuned; tuning.

Old English up, uppe, from Proto-Germanic *upp- "up" (source also of Old Frisian, Old Saxon up "up, upward," Old Norse upp; Danish, Dutch op; Old High German uf, German auf "up"; Gothic iup "up, upward," uf "on, upon, under;" Old High German oba, German ob "over, above, on, upon"), from PIE root *upo "under," also "up from under," hence also "over."

As a preposition, "to a higher place" from c. 1500; also "along, through" (1510s), "toward" (1590s). Often used elliptically for go up, come up, rise up, etc. Up the river "in jail" first recorded 1891, originally in reference to Sing Sing, which is up the Hudson from New York City. To drive someone up the wall (1951) is from the notion of the behavior of lunatics or caged animals. Insulting retort up yours (scil. ass) is attested by late 19c.