Definition of up- in US English:

up-

prefix

  • 1(added to verbs and their derivatives) upward.

    ‘upturned’
    ‘upthrow’
    1. 1.1 To a more recent time; to a newer or better state.
      ‘update’
      ‘upbeat’
      ‘upgrade’
      ‘upscale’
  • 2(added to nouns) denoting (direction of) motion up.

    ‘upriver’
    ‘uphill’
    ‘upwind’
  • 3(added to nouns) higher.

    ‘upland’
    ‘upstroke’
    1. 3.1 Increased.
      ‘up-tempo’

Pronunciation

up-

/əp/