18-letter words containing r, o, t, h, l
- oriental cockroach — a dark-brown cockroach, Blatta orientalis, thought to have originated in Asia but now nearly cosmopolitan in distribution.
- oriental shorthair — any of a breed of domestic cat, similar to the Siamese but with greenish eyes and often a coat of a solid color
- orthophthalic acid — Chemistry. any of three isomeric acids having the formula C 8 H 6 O 4 , especially the ortho isomer (orthophthalic acid) a colorless, crystalline, slightly water-soluble solid used chiefly in the manufacture of dyes, medicine, and perfume.
- over the long term — in the future
- overnight telegram — a type of domestic telegram sent at a reduced rate with a minimum charge for 10 words or less and accepted until midnight for delivery the following day.
- palaeoanthropology — the branch of anthropology concerned with primitive man
- parathyroid glands — any of several small oval glands usually lying near or embedded in the thyroid gland.
- peter and the wolf — a composition by Sergei Prokofiev written in 1936. It is a children's story with both music and text, spoken by a narrator accompanied by the orchestra
- phanerocrystalline — (of a rock) having the principal constituents in the form of crystals visible to the naked eye.
- phantasmagorically — having a fantastic or deceptive appearance, as something in a dream or created by the imagination.
- phantom withdrawal — the unauthorized removal of funds from a bank account using an automated teller machine
- philharmonic pitch — a standard of pitch in which A above middle C is established at 440 vibrations per second.
- phosphatidylserine — any of a class of phospholipids occurring in biological membranes and fats
- photoelectric cell — photocell.
- physical inventory — To carry out a physical inventory is to count all the stock on hand.
- pick of the litter — objects strewn or scattered about; scattered rubbish.
- planned parenthood — an organization that gives out information on the planning of the number and spacing of the births of one's children, as through the use of birth-control measures
- plight one's troth — to make a promise of marriage
- pollen mother cell — one of the mother cells that produce four microspores by meiosis.
- polychromatophilic — having an affinity for more than one kind of stain, especially for acid, neutral, and basic stains, as polychromatophilic erythroblasts characteristic of pernicious anemia.
- positively charged — having a positive charge
- potassium chlorate — a white or colorless, crystalline, water-soluble, poisonous solid, KClO 3 , used chiefly as an oxidizing agent in the manufacture of explosives, fireworks, matches, bleaches, and disinfectants.
- potassium chloride — a white or colorless, crystalline, water-soluble solid, KCl, used chiefly in the manufacture of fertilizers and mineral water, and as a source of other potassium compounds.
- preparatory school — a private or parochial secondary school, especially one boarding its students and providing a college-preparatory education.
- probability theory — the theory of analyzing and making statements concerning the probability of the occurrence of uncertain events. Compare probability (def 4).
- psychogalvanometer — a type of galvanometer for detecting and measuring psychogalvanic currents.
- random walk theory — the theory that the future movement of share prices does not reflect past movements and therefore will not follow a discernible pattern
- residential school — (in Canada) a boarding school maintained by the Canadian government for Indian and Inuit children from sparsely populated settlements
- return to the fold — come back home
- reverse angle shot — Movies. reverse shot.
- rhode island white — one of a dual-purpose American breed of chickens having white feathers and a rose comb.
- right-to-work laws — a state law making it illegal to refuse employment to a person for the sole reason that he or she is not a union member.
- root canal therapy — endodontics.
- rotary clothesline — an apparatus of radiating spokes that support lines on which clothes are hung to dry
- rub shoulders with — to mix with socially or associate with
- rubbish collection — the collection of domestic refuse for disposal
- salt of phosphorus — a colorless, odorless, crystalline, water-soluble solid, NaNH 4 HPO 4 ⋅4H 2 O, originally obtained from human urine: used as a blowpipe flux in testing metallic oxides.
- school certificate — (in England and Wales between 1917 and 1951 and currently in New Zealand) a certificate awarded to school pupils who pass a public examination: the equivalent of GCSE
- school of motoring — a centre where people pay for lessons to learn to drive
- sell oneself short — If you sell someone short, you do not point out their good qualities as much as you should or do as much for them as you should.
- september holidays — a period of time in September when people do not have to go to school, college or work
- shatterproof glass — glass designed to resist shattering
- sheltered workshop — a place of employment for persons with disabilities where their rights are protected and their needs are met.
- shop till you drop — If you shop till you drop, you do a large amount of shopping.
- short-tailed shrew — a grayish-black shrew, Blarina brevicauda, common in eastern North America, that has a tail less than half the length of the body.
- shugart technology — Seagate Technology
- sindbad the sailor — (in The Arabian Nights' Entertainments), a wealthy citizen of Baghdad who relates the adventures of his seven wonderful voyages.
- sixth-form college — (in England and Wales) a college offering A-level and other courses to pupils over sixteen from local schools, esp from those that do not have sixth forms
- sling psychrometer — a psychrometer so designed that the wet-bulb thermometer can be ventilated, to expedite evaporation, by whirling in the air.
- spectroheliography — the process of obtaining an image of the sun in light of a particular wavelength, such as calcium or hydrogen, showing the distribution of the element over the surface and in the solar atmosphere, using a spectroheliograph