Meaning of ACT UP in English

ACT UP

transcription, транскрипция: [ intransitive verb ]

Date: 1903

1. : to act in a way different from that which is normal or expected: as

a. : to behave in an unruly, recalcitrant, or capricious manner

the children were acting up

b. : show off

c. : to function improperly

this typewriter is acting up again

2. : to become active or acute after being quiescent

her rheumatism started to act up

Merriam-Webster's Collegiate English vocabulary.      Энциклопедический словарь английского языка Merriam Webster.