The abbreviation SOS most commonly means "Save Our Souls" or "Save Our Ship." It is an internationally recognized distress signal used in emergencies, especially in maritime and aviation contexts, to call for help.

Key points about SOS:

• It is a Morse code signal: three short signals, three long signals, three short signals (· · · - - - · · ·).
• It does not stand for any specific words officially; "Save Our Souls" is a popular backronym.
• Used universally as a call for urgent assistance.

If you meant something else by "SOS only," please let me know!