TOS

In real, traceable use. Part of the curated seed collection; community review is coming.

Meaning · English

Initialism of the old series or the original series.

Register: slang

Where it’s used: Used American English

Examples

Star Trek: TOS; Battlestar Galactica: TOS

Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30)

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).

Common questions

What does “TOS” mean?

Initialism of the old series or the original series.

Is “TOS” formal or informal?

TOS is generally slang.