Tail Signals

Tail is curved gently downward and then curves up again at the tip.
The cat is relaxed and at peace with the world.

Tail is raised slightly and softly curved.
The cat is beginning to get interested in something.

Tail is held erect, but tip is tilted over.
The cat is very interested and is in a friendly mood, but has slight reservations.

Tail is fully erect, and tip is stiffly vertical.
The cat is offering an intense greeting without reservations.

Tail is erect with whole length quivering gently.
The cat is displaying affection, as in response to a greeting by a favored human.

Tail is held still, but tip is twitching slightly.
The cat is mildly irritated.

Tail is held still, but tip is twitching vigorously.
The cat is very irritated, and a bad-tempered paw swipe is about to occur.

Tail is swishing vigorously from side to side.
The cat is angry and about to attack.

Tail is held straight and fully bristled.
The cat is aggressive.

Tail is arched and bristled.
The cat is defensive and may attack if provoked further.

Tail is lowered and fluffed out.
The cat is indicating an active fear.

Tail is fully lowered and may be tucked between hind legs.
The cat is giving a signal of defeat or total submissiveness.

Tail is held to one side.
The female cat in heat is inviting a sexual encounter.

The above list of tail signals is an adaptation of unattributed lists seen in various forms on the Internet. If there is a known author, please let me know and I will be glad to give credit.