A type of player commonly found on the virtual kids game roblox, they primarily wear military uniforms either fictional or real world (but many tend to wear real world uniforms.) These uniforms are either formal or non formal.
They are sometimes found on games that involve firearms, like phantom forces, bad business, etc. They could also be found on other games of many different genres.

A recent game that contains milsims is the Church, a game filled with homophobes, racists, rednecks, white suprematists, etc.
Over there my friend, is a milsim in its virtual habitat.
by the roblox “historian” January 4, 2021
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MilSims (FPS) are games specifically coded to be as accurate to modern military combat as possible. Great examples for this genre of video games are Squad, Arma III, the Insurgency Series, Escape From Tarkov, and many more. These are also the types of games to make you bored as hell, and entertained as hell. For a better example, you can walk 15 miles only to get shot by a 12 year old 56 miles away. Or you can be dodging bullets in a Afghani suburb. But most of the time you'll just be walking around doing senseless shit the entire round.
Jake: Have you seen John lately?

Jane: No, he hasn't even texted me at all this week. He said, "stfu bich im playing milsims (fps) btw stupid with the boys" then stopped talking to me.
by Hecking Degenerate November 21, 2020
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