By default, anyone can see a list of Meetup groups you're a member of on your profile. You can hide this list of groups from your profile in your privacy settings. Your membership in a Meetup group may still be visible in other places depending on the group's content visibility settings.
To hide your list of groups on your profile, follow these steps:
Desktop/mobile web
Click the circular profile button in the top right-hand, and then Settings
Click Edit Profile
Scroll down and toggle Show Meetup groups
Click Save Changes
iOS/Android apps
From the Home tab, tap your profile icon in the top right corner.
Tap the "..." three dots icon in the top right corner.
Tap Edit my profile.
Scroll down to Privacy and toggle Show groups on profile.