tapetum.noun
a membranous layer, especially the iridescent (rainbow like colors) choroid (vascular membrane that forms the middle coat of the eye, between the sclera {white of the eye} and the retina) membrane in the eyes of certain animals, as the cat

tactics.noun.plural
any skillful methods employed to gain an end
tactical.adjective
of, relating to, or using tactics; of, relating to, used in, or involving military or naval operations that are smaller, closer to base, and of less long term significance than strategic operations; carried out in support of military or naval operations (tactical bombing); characterized by adroitness, ingenuity, or skill
tactically.adverb

teleological.adjective
concerned with design or purpose in nature as relating to final causes
teleology.noun
the study of final causes; the study of evidences of design in nature; a doctrine (as in vitalism) that ends are immanent in nature, that purpose is involved; a doctrine explaining phenomena by final causes; the fact or character attributed to nature or natural processes of being directed toward an end or shaped by a purpose; the use of design or purpose as an explanation of natural phenomena 
teleologist.noun

teleonomy.noun
the quality of apparent purposefulness in living organisms that derives from their alleged-evolutionary-adaptation
teleonomic.adjective

transition.noun
passing from one stage, form, activity, place, etc., to another; 
Paleontology.–.a fossil of which can be said representation exhibits (shows) a form that lies between two fundamentally different structures and functions in an actual evolutionary line of descent, or that is directly ancestral to any such fundamentally different species
transitional.adjective

temerity.noun
foolish boldness; foolhardiness; recklessness; rashness 
temerity referes to a boldness that fails to evaluate the consequences
temerarious.noun
synonym-gall

testimony.noun
an affirmation or declaration; a declaration made to establish a fact 
testimonial.noun
a written statement testifying as to a person's qualifications, abilities and character 

transpose, transposed, transposing, transposes.verbs
to reverse or transfer the order or place of; interchange; to put into a different place or order; to alter in form or nature; transform
transposable.adjective

transposon.noun
a transposable element especially when it contains genetic material controlling functions other than those related to its relocation

transvalue, transvalued, transvaluing.transitive verbs
to evaluate by a new principle, one rejecting conventional or accepted standards 

tauons
the tau neutrino is the most massive lepton at 3,000 times the mass of an electron, with a very short lifetime of 10^-13 seconds

tomography-noun
a method of making X-ray photographs of a selected plane of the body; a method of producing a three dimensional image of the internal structures of a solid object (as the human body or the earth) by the observation and recording of the differences in the effects on the passage of waves of energy impinging on those structures – compare computerized assisted or, axial tomography (CAT) scan and positron emission tomography (PET)
tomographic-adjective
radiography in which a three dimensional image of a body structure is constructed by computer from a series of plane cross sectional images made along an axis-– called also computed axial tomography, computerized axial tomography, computerized tomography 
tomographically.adverb

transform, transformed, transforming, transforms.verbs
to change the form or outward appearance of something external or in inner nature (she was transformed into a happy girl)
transitive use-change markedly the appearance or form of; to change the nature, function, or condition of; convert
intransitive use.to undergo a transformation
transform.noun
the result, especially a mathematical quantity or linguistic (the study of the nature and structure of human speech) construction, of a transformation
transformable.adjective

transformation.noun
the act or an instance of transforming; the state of being transformed; a marked change, as in appearance or character, usually for the better; a mapping of one space onto another or onto itself; a construction derived by such transformation; a transform
transformative, transformational.adjectives
Genetics.-.alteration of a bacterial cell by introduction of DNA from another cell or from a virus
Linguistics.-.the process of converting a syntactic construction into a semantically equivalent construction according to the rules shown to generate the syntax of the language
transformationalgrammar.noun
a grammar that accounts for the constructions of a language by linguistic transformations and phrase structures, especially generative transformational grammar
Mathematics.-.replacement of the variables in an algebraic expression by their values in terms of another set of variables

transmogrify.transitive verb
to transform in a grotesque or strange manner 
transmogrification.noun
a transmogrifying or being transmogrified

transmute, transmuted, transmuting, transmutes.verbs
intransitive use.to change from one form, nature, substance, or state into another (the way to change lead into gold); transform; convert
intransitive use.to undergo transmutation
transmutability.or.transmutableness.noun
change of one thing into another; the conversion of one element into another, as in radioactive-disintegration or by nuclear bombardment
transmutable.adjective
transmutably.adverb
transmuter.noun

transmutation.noun
the act or an instance of transmuting; transformation; the state of being transmuted
Physics.-.transformation of one element into another by one or a series of nuclear reactions; the conversion of base metals into gold or silver in alchemy
transmutational.or.transmutative.adjective
tending to transmute; having to do with transmutation
transmutation, transmutability.nouns

trust.noun
total confidence in the honesty, integrity, reliability, justice, etc. of another person or thing; entrusting one's self into another's care

thereby.adverb
by that means; because of that; in connection with that

titter, tittered, tittering, titters.intransitive verbs
to laugh in a restrained, nervous way; giggle
titter, titterer.nouns
a nervous giggle
titteringly.adverb

thorough.adjective
exhaustively complete (a thorough search); painstakingly accurate or careful (thorough research)
thorough.preposition
thorough, thoroughly.adverbs
thoroughness.noun