15-letter words containing o, y, s, t, e, r
- theory of types — a theory advanced by Bertrand Russell to avoid the liar paradox, Russell's paradox, etc, in which a class of expressions or of the entities they represent can all enter into the same syntactic relations
- thermochemistry — the branch of chemistry dealing with the relationship between chemical action and heat.
- thirtysomething — a person in her or his thirties
- to do your best — If you do your best or try your best to do something, you try as hard as you can to do it, or do it as well as you can.
- traveller's joy — a ranunculaceous Old World climbing plant, Clematis vitalba, having white flowers and heads of feathery plumed fruits
- treaty of paris — a treaty of 1763 signed by Britain, France, and Spain that ended their involvement in the Seven Years' War
- tricotyledonous — having three cotyledons.
- trust territory — a territory under the administrative control of a country designated by the United Nations.
- tutorial system — a system of education, especially in some colleges, in which instruction is given personally by tutors, who also act as general advisers of a small group of students in their charge.
- unadventurously — in an unadventurous manner
- unconstrainedly — in an unconfined manner
- unpretentiously — without pretension
- up to your ears — If you are up to your ears in something, it is taking up all of your time, attention, or resources.
- up to your eyes — If you say that you are up to your eyes in something, you are emphasizing that you have a lot of it to deal with, and often that you are very busy.
- vector analysis — the branch of calculus that deals with vectors and processes involving vectors.
- voyeuristically — of, relating to, or characteristic of a voyeur or of voyeurism.
- winter holidays — a period of rest from work or studies taken in winter
- wolf-rayet star — a very hot (35,000–100,000 K) and luminous star in the early stages of evolution, with broad emission lines in its spectrum.
- youth orchestra — an orchestra that is made up of young musicians