18-letter words containing p, h, o, t, i, d
- sonic depth finder — a sonar instrument that uses echolocation to measure depths under water.
- southampton island — an island in N Canada, in the Northwest Territories at the entrance to Hudson Bay. 19,100 sq. mi. (49,470 sq. km).
- the encyclopedists — the writers of the French Encyclopedia (1751-72) edited by Diderot and d'Alembert, which contained the advanced ideas of the period
- the operative word — If you describe a word as the operative word, you want to draw attention to it because you think it is important or exactly true in a particular situation.
- thiosulphuric acid — an unstable acid known only in solutions and in the form of its salts. Formula: H2S2O3
- to pick and choose — If you pick and choose, you carefully choose only things that you really want and reject the others.
- triphosphoric acid — the hypothetical acid H 5 P 3 O 10 , known chiefly by its salts.
- vectorcardiography — a method of determining the direction and magnitude of the electrical forces of the heart.
- white-spotted hyla — a type of tree frog (H. leucophyllata) of tropical America
- withdrawal symptom — effects of stopping a drug