16-letter words containing p, o, t, a
- twofold purchase — a purchase using a double standing block and a double running block so as to give a mechanical advantage of four or five, neglecting friction, depending on whether the hauling is on the standing block or the running block.
- typhoid bacillus — the bacterium Salmonella typhosa, causing typhoid fever.
- ultramicroscopic — an instrument that uses scattering phenomena to detect the position of objects too small to be seen by an ordinary microscope.
- unapologetically — containing an apology or excuse for a fault, failure, insult, injury, etc.: An apologetic letter to his creditors explained the delay.
- uncinate process — a curved, bony process on certain ribs of birds that projects backward and overlaps the succeeding rib, serving to strengthen the thorax.
- undercompensated — to compensate or pay less than is fair, customary, or expected.
- unproportionally — having due proportion; corresponding.
- up to one's ears — the organ of hearing and equilibrium in vertebrates, in humans consisting of an external ear that gathers sound vibrations, a middle ear in which the vibrations resonate against the tympanic membrane, and a fluid-filled internal ear that maintains balance and that conducts the tympanic vibrations to the auditory nerve, which transmits them as impulses to the brain.
- upper atmosphere — the portion of the atmosphere above the troposphere.
- upsilon particle — the 20th letter of the Greek alphabet (Υ, υ).
- vapor combustion — Vapor combustion is a closed burn system used for treating liquid waste which contains volatile organic compounds.
- vegetable sponge — loofah (def 2).
- ventriculography — radiography of the ventricles of the heart after injection of a contrast medium
- vest-pocket park — pocket park.
- voluntary helper — a person who aids or assists in a specified function of one's own accord and without compulsion or promise of remuneration
- walk a tightrope — be in a precarious position
- watch one's step — a movement made by lifting the foot and setting it down again in a new position, accompanied by a shifting of the weight of the body in the direction of the new position, as in walking, running, or dancing.
- well-compensated — to recompense for something: They gave him ten dollars to compensate him for his trouble.
- white propaganda — propaganda that comes from the source it claims to come from
- willow ptarmigan — a ptarmigan, Lagopus lagopus, of arctic and subarctic regions of the New and Old Worlds, having brown, mottled plumage in summer and white plumage in winter.
- windfall profits — Windfall profits are excessive profits with a non-business cause such as a natural disaster.
- wipe off the map — to put out of existence
- writ of subpoena — a legal document commanding the attendance in court, as a witness, of the person on whom it is served, under a penalty
- x-ray photograph — a radiograph made with x-rays.
- xenotransplanted — Transplanted by xenotransplantation.
- yah-boo politics — adversarial politics in which politicians constantly deride their opponents and dismiss everything suggested by them