The massive global response was triggered by the allegations against Hollywood mogul Harvey Weinstein, who is accused of rape and abuse dating back decades.
People shared stories and offered support under multiple hashtags, including #MeToo in English, #balancetonporc ("Rat out your pig") in French, and #quellavoltache ("That time that") in Italian.
American actress Alyssa Milano on Sunday sparked the outpouring with a simple Twitter request that women respond "me too" if they have also been sexually harassed or assault.
Tens of thousands of people replied, making #MeToo the top trending topic.
The posts continued to accumulate Monday, with the intensity of the social media response sharply underscoring the problem's breadth -- implicating fashion, entertainment, politics and the lives of everyday people.
Monica Lewinsky -- who was at the center of the White House sex scandal in the 1990s leading to the impeachment trial of former US President Bill Clinton -- simply tweeted the hashtag #MeToo without comment.
More Celebrities Chime In
Responding to Milano's call, Lady Gaga and Sheryl Crow were among those from the music world tweeting their support.
Crow on Monday shared her experience of improper behavior by a manager "on my first big tour as a backup singer."
"When I went to a lawyer he told me to suck it up bc the guy could do a lot for me," Crow tweeted, "so I wrote songs about it on my first record."
Actress Evan Rachel Wood wrote of being raped more than once, writing, "I instinctually shut down. My body remembered, so it protected me. I disappeared. #metoo."
Prior to Milano's call, American fashion model Cameron Russell took to Instagram last week asking her followers to share experiences of sexual abuse in her industry, using the hashtag #MyJobShouldNotIncludeAbuse.
She has been tweeting some of the hundreds of responses, anonymous stories ranging from recent experiences to some dating back two decades -- primarily involving women, sometimes minors, and occasionally men.
"Hearing about #harveyweinstein this week has sparked conversations about how widespread and how familiar his behavior is," the model and activist wrote.
"We are speaking to each other, we are speaking up, we are speaking to lawyers, and we are speaking to well-resourced reporters," she added.
"Molested by a family member. Raped as a kid and an adult. Became a drug addict and then overcame. Don't ever give up. I'm here#MeToo," wrote a woman identified as Amy Christensen on her Twitter account.
There were many sympathetic responses from men.
Vinay Ramesh, a tech entrepreneur, encouraged "all my fellow men to learn about #MeToo. The responsibility to stop sexual violence is absolutely on us."
Around The World
Italian actress Asia Argento, who has accused Weinstein of sexual abuse, offered another bombshell, saying a Hollywood director had raped her and that an Italian director had exposed himself to her when she was a minor.
"Hollywood big shot director with Napoleon complex gave me GHB (the "date rape" drug) and raped me unconscious. I was 26 years old," she tweeted using the hashtag #quellavoltache, in remarks that sparked outrage in her home country.
Argento did not name either of the men she accused.
In France, the top-trending hashtag #balancetonporc, started by journalist Sandra Muller, brought forth stories from women of being sexually harassed at work or in the street.
Muller began the hashtag recounting how her former boss had called her "my type of woman" and then commented on her breasts.
In Britain, Labour MP Stella Creasy tweeted her own claims of harassment, "like millions of women & girls all around the world. Shame is on the attackers, not me."
Similar stories spread in the Arab world, from Tunisia to Egypt and Dubai, describing incidents suffered by women at work or in public spaces, and denouncing "rape culture".
More than 20 women -- a who's who of Hollywood -- have come forward to accuse Weinstein of rape, assault and sexual harassment.
Weinstein, who insists any sexual encounters were consensual, was expelled last week from the Academy of Motion Picture Arts and Sciences.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)