up (adv.)

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.

up (v.)

1550s, "to drive and catch (swans)," from up (adv.). Intransitive meaning "get up, rise to one's feet" (as in up and leave) is recorded from 1640s. Sense of "to move upward" is recorded from 1737. Meaning "increase" (as in up the price of oil) is attested from 1915. Compare Old English verb uppian "to rise up, swell." Related: Upped; upping. Upping block, used for mounting or dismounting horses, carriages, etc., is attested from 1796 (earlier was horsing-block, 1660s).

up (adj.)

c. 1300, "dwelling inland or upland," from up (adv.). Meaning "going up" is from 1784. From 1815 as "excited, exhilarated, happy," hence "enthusiastic, optimistic." Up-and-coming "promising" is from 1848. Musical up-tempo (adj.) is recorded from 1948.

up (n.)

"that which is up," 1530s, from up (adv.). Phrase on the up-(and-up) "honest, straightforward" first attested 1863, American English.

Definitions of up
up (adj.)
(usually followed by `on' or `for') in readiness;
he was up on his homework
had to be up for the game
up (adj.)
(used of computers) operating properly;
how soon will the computers be up?
up (adj.)
used up;
time is up
up (adj.)
extending or moving toward a higher place;
the up staircase
Synonyms: upward
up (adj.)
out of bed;
up by seven each morning
Synonyms: astir
up (adj.)
being or moving higher in position or greater in some value; being above a former position or level;
the sun is up
the market is up
the anchor is up
the corn is up
he is up by a pawn
he lay face up
up (adj.)
getting higher or more vigorous;
its an up market
Synonyms: improving
up (adj.)
the windows are up
up (adv.)
spatially or metaphorically from a lower to a higher position;
look up!
the music surged up
Synonyms: upwards / upward / upwardly
up (adv.)
to a higher intensity;
he turned up the volume
up (adv.)
nearer to the speaker;
he walked up and grabbed my lapels
up (adv.)
to a more central or a more northerly place;
up to Canada for a vacation
was transferred up to headquarters
up (adv.)
to a later time;
they moved the meeting date up
Synonyms: upwards / upward
up (v.)
up the ante