act up

malfunction, operate abnormally; behave strangely or abnormally; behave in a disorderly manner, behave disobediently; show off, behave in a way that draws attention to oneself

ACT UP, or the AIDS Coalition to Unleash Power, "is a diverse, non-partisan group of individuals ... committed to direct action to end the AIDS crisis." - from the ACT UP/New York website.ACT UP was effectively formed on March 10, 1987 at the Lesbian and Gay Community Services Center in New York. Larry Kramer was asked to speak as part of a rotating speaker series, and his well-attended speech focused on action to fight AIDS. Kramer spoke out against the Gay Men's Health Crisis (GMHC), which he perceived as politically impotent. Kramer had co-founded the GMHC but had resigned from its board of directors in 1983. According to Douglas Crimp, Kramer posed a question to the audience: "Do we want to start a new organization devoted to political action?" The answer was "a resounding yes." Approximately 300 people met two days later to form ACT UP.
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Verb
1. misbehave badly; act in a silly or improper way; "The children acted up when they were not bored"
(synonym) carry on
(hypernym) misbehave, misconduct, misdemean
2. make itself felt as a recurring pain; "My arthritis is acting up again"
(hypernym) ache, smart, hurt

not work right, give pain or problems My stomach is acting up today. I don't feel well.

FARE I CAPRICCI. FUNZIONARE MALE. COMPORTARSI MALE