General science terms:
* Theory: A well-substantiated explanation of some aspect of the natural world.
* Technology: The application of scientific knowledge for practical purposes.
* Taxonomy: The science of classifying organisms.
* Thermodynamics: The branch of physics that deals with heat and its relation to other forms of energy.
* Telescope: An instrument used to view distant objects.
Biology:
* Tissue: A group of similar cells that perform a specific function.
* Transcription: The process of copying a gene's DNA sequence into RNA.
* Translation: The process of converting an RNA sequence into a protein.
* Turgor pressure: The pressure exerted by water inside a plant cell against its cell wall.
Chemistry:
* Titration: A laboratory technique used to determine the concentration of a substance.
* Temperature: A measure of the average kinetic energy of the particles in a system.
* Transition metal: An element whose atoms have an incomplete d sublevel.
* Titration: A technique for determining the concentration of a solution by reacting it with a solution of known concentration.
Physics:
* Torque: A twisting force that causes rotation.
* Time: A fundamental quantity in physics that measures the duration of events.
* Trajectory: The path followed by a projectile.
Geology:
* Tectonics: The study of the deformation of the Earth's crust.
* Tsunami: A series of waves caused by an earthquake or other disturbance in the ocean.
This is just a small sample of the many science words that start with "t". What specific field are you interested in? This could help me provide more relevant examples.