Three-O
Short for when a surfer rotates three hundred and sixty degrees.

Three Sixty
When a surfer completely rotates the board on a horizontal plane while continuing to surf. A rotation of the nose towards the collapsing peak is an inside 360. A rotation of the nose away from the collapsing peak is an outside 360.

Throwin'
Spraying a rooster tail fan as the result of a particularly sharp gashing turn.

Throwin' Heat
Used in place of ripping to describe someone who is surfing well.

Throwin' Tail
Sliding the tail of a surfboard in a turn breaking the grip of the fins.

Thrurster
Three-fin surfboard design created by Simon Anderson of Australia in 1980; now the most common fin setup used by surfers, the Thruster combines drive and control in most surfing situations.

Tidal Bore
Large fast moving wave caused by an extreme tide influence as water collides and overtakes out flowing water from rivers or estuaries. The one most known about and surfed occurs in the Amazon. It's called the poroc-poroc in the native Tupi Indian dialect. Translated to Pororoca; this phenomena occurs at the end of the dry season when the full moon sets in the west. The "great roar" as it's known to locals, happens twice a day a couple of times a year.

Tigre
The Peruvian moniker for a surfer that's ripping.

Time Travel
Tube ride, shack time, spending time in the Green Room.

Tint
Chemical used to color the resin used to seal fiberglass onto a conventional surfboard; largely replaced by airbrush paints through the 1980s, but still used in some quarters for its unique retro look.

Tit Rash
Condition precipitated by friction resulting from direct skin contact with board decks, aggravated by infusions of salt water.

Titanium
A soft metal occasionally weaved into neoprene as early as '91, supposedly to reflect heat back to the wearer.

Toe In
Angling of fins to cause pressure on the outside to be greater than on the inside. Makes a board more responsive and is used to eliminate the tracking characteristic of early twin fin setups.

Toes on the Nose
To ride a wave with your toes curled over the nose of the board.

Tombstoning
A post-wipeout phenomenon, when a surfer is deep underwater with the surf leash stretched out to a point where the tail of the surfboard is being pulled down, so the nose of the surfboard sticks up in the air like a tombstone. Usually happens in larger surf.

Tonked
To get wrecked, worked, rag dolled, etc.

Top Turn
Similar to a re-entry but the approach is less vertical and usually done to gain speed.

Tow In
Being towed into waves by boat or PWC that are usually too large to paddle into.

Tow Surfing
The act of towing into waves behind a personal watercraft instead of paddling into waves. A major pull for big-wave surfing.

Towboard
A surfboard designed specifically to be used during tow-in surfing, usually in very big surf; usually marked by drastic reductions in length, width and thickness, and by equally drastic additions to overall weight through ultra-heavy blanks and glass jobs. Towboards often feature footstrap setups, not unlike sailboards and/or kiteboards.

Trace
A weak or slight swell that's almost unnoticeable until it reaches very shallow water. Usually caused by surface winds, as opposed to long period swell which are caused by low pressure systems.

Traction Pad
Rubber/foam pad applied to tail area of a surfboard to assist the surfer in maintaining traction.

Trade Winds
Two belts of prevailing winds that blow easterly from the subtropical high pressure centers toward the equatorial trough. Primarily lower level winds, they are characterized by their great consistency of direction. In the Northern Hemisphere, the trades blow from the northeast, and in the Southern Hemisphere, the trades blow from the southeast.