Matt Damon is rocking some new ink ... of the word "Nomad" on his shoulder — and of Damon giving him a tattoo back! "Got to tattoo an idol of mine!," Winter wrote alongside the video.

Everyone needs a friend like Chris Hemsworth — just ask Matt Damon ... that Damon also picked up the tattoo machine and tattooed Winter right back. "And Mr. Damon tattooed me!

When Matt Damon got a new tattoo earlier this month, he was glad to have a helping hand from his pal Chris Hemsworth. In photos posted on Instagram by Los Angeles-based tattoo artist Trudy Lines ...

The two appeared in "Thor: Ragnarok" and "Thor: Love and Thunder" together. Thor and (fake) Loki are now brothers in ink! Matt Damon received some strong support from none other than Chris ...

The entertainment industry's favorite tattoo artist "winterstone" who has ... are permanent designs on the bodies of Lady Gaga, Matt Damon, Miley Cyrus, and a slew of other celebrities.