18-letter words containing h, r, d, i, a
- three-day eventing — participation in a three day equestrian competition consisting of dressage, cross-country jumping, and stadium jumping
- thrills and spills — If you refer to thrills and spills, you are referring to an experience which is exciting and full of surprises.
- to a grinding halt — If you describe a bad situation as grinding, you mean it never gets better, changes, or ends.
- to be said for sth — If you say there is a lot to be said for something, you mean you think it has a lot of good qualities or aspects.
- transit theodolite — a theodolite having a telescope that can be transited.
- triarylmethane dye — any of the class of dyes containing three aryl groups attached to a central carbon atom: used chiefly for dyeing cotton, wool, and silk.
- triphosphoric acid — the hypothetical acid H 5 P 3 O 10 , known chiefly by its salts.
- under the aegis of — guided or protected by
- urban homesteading — homesteading (def 2).
- vectorcardiography — a method of determining the direction and magnitude of the electrical forces of the heart.
- water of hydration — the portion of a hydrate that is represented as, or can be expelled as, water: now usually regarded as being in true molecular combination with the other atoms of the compound, and not existing in the compound as water.
- white man's burden — the alleged duty of white colonizers to care for nonwhite indigenous subjects in their colonial possessions.
- white-faced hornet — any large, stinging paper wasp of the family Vespidae, as Vespa crabro (giant hornet) introduced into the U.S. from Europe, or Vespula maculata (bald-faced hornet or white-faced hornet) of North America.
- withdrawal symptom — effects of stopping a drug
- world championship — an international competition in a particular sport or activity for people all around the world
- xenon hexafluoride — a colorless, crystalline compound, XeF 6 , that melts at 50°C to a yellow liquid, and boils at 75°C.