PC.net

TOS

Meaning The Original Series
Type Acronym
Rank ★ ☆ ☆  Uncommon
Usage Online Only (chat, messaging, e-mail)
Comments

Most likely refers to "Star Trek: The Original Series"

Example "Which series did you like better - Star Trek TOS or TNG?"
Updated February 23, 2021
Information from PC.net
https://pc.net/slang/meaning/tos
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