(informal) Legitimate; honest; upright.

Alternative spelling of on the up-and-up

(idiomatic) Willing to participate in; interested in. / (idiomatic) Being or due to be evaluated, inspected, judged, considered, sold, etc., in the stated circumstances or by the stated method.

(idiomatic) To do or be involved in doing; to do (often something mischievous or inappropriate). / (idiomatic) To depend on, to be the choice of.

(uncountable) The direction opposed to the pull of gravity. / (countable) A positive thing, or a time or situation when things are going well. / (particle physics) An up quark.

Away from the surface of the Earth or other planet; in opposite direction to the downward pull of gravity. / To or at a physically higher or more elevated position.

(transitive, poetic or in certain phrases) To physically raise or lift. / (transitive, colloquial) To increase the level or amount of. / (transitive, colloquial) To promote.

Toward the top of. / Toward the center, source, or main point of reference; toward the end at which something is attached. / From south to north of. / Further along (in any direction).

Facing upwards. / On or at a physically higher level. / Headed or designated to go upward (as an escalator, stairway, elevator etc.) or toward (as a run-up).

(idiomatic, colloquial) Well-informed concerning.