Well, we seem to be drifting gently towards the end of the alphabet, time for T =]

taniwha - a mythical monster which, according to Maori legend, lives in very deep water

tappen - the plug by which the rectum of a bear is closed during hibernation (well that's something we all wanted to know)

tellurian - of or inhabiting the earth, or an inhabitant of the earth

testudo - a device used in siege warfare in ancient Rome, consisting of a wheeled screen with an arched roof, literally a 'tortoise'

thalassic - relating to the sea

thaumatrope - a scientific toy devised in the 19th century. It consisted of a disc with a different picture on each of its two sides: when the disc was rotated rapidly about a diameter, these pictures appeared to combine into one image.

thirstland - S. African a desert or large arid area

thrutch - N. English a narrow gorge or ravine (and you don't want to get caught unprotected in the thrutch area)

thurifer - a person carrying a censer, or thurible, of burning incense during religious ceremonies

tiffin - chiefly Indian a light meal, especially lunch

tigon - the hybrid off spring of a male tiger and a lioness (the offspring of a male lion and a tigress being a liger)

tokoloshe - in African folklore, a mischievous and lascivious hairy water sprite

toplofty - N. Amer. informal haughty and arrogant

transpicuous - transparent

triskaidekaphobia - extreme superstition about the number thirteen (I used to live in a house that was No. 15. The houses on either side were 11 and 17, it seems No. 13s in house building don't sell so well, a bit like green cars. I actually quite fancied living at 13.)

triskelion - a Celtic symbol consisting of three radiating legs or curved lines, such as the emblem of the Isle of Man

tsantsa - a human head shrunk as a war trophy by the Jivaro people of Ecuador

turbary - the legal right to cut turf or peat for fuel on common ground or on another person's ground