21-letter words containing p, l, a, g
- supergranulation cell — one of a number of large convection cells in the photosphere and chromosphere of the sun, each having a diameter of 10,000–20,000 miles (16,000–32,000 km) and lasting longer than a day.
- threshold wage policy — a policy whereby wages are increased in accordance with inflation
- to move the goalposts — If you accuse someone of moving the goalposts, you mean that they have changed the rules in a situation or an activity, in order to gain an advantage for themselves and to make things difficult for other people.
- topgallant forecastle — a partial weather deck on top of a forecastle superstructure; forecastle deck.
- topological invariant — a property of a topological space that is a property of every space related to the given space by a homeomorphism.
- traveling salesperson — a representative of a business firm who travels in an assigned territory soliciting orders for a company's services.
- wildlife photographer — someone that specializes in taking photographs of wild animals, especially in their natural habitats, and plants
- x-ray crystallography — the determination of the structure of a crystal by the use of x-ray diffraction.