from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A round mass.
  • noun A single, relatively large quantity of a substance, such as a dose of a drug, intended for therapeutic use and taken orally.
  • noun A concentrated mass of a substance administered intravenously for diagnostic or therapeutic purposes.
  • noun A soft mass of chewed food within the mouth or digestive tract.

from The Century Dictionary.

  • noun A soft round mass of anything medicinal, larger than an ordinary pill, to be swallowed at once.
  • noun Figuratively, anything disagreeable, as an unpalatable doctrine or argument, that has to be accepted or tolerated.

from the GNU version of the Collaborative International Dictionary of English.

  • noun A rounded mass of anything, esp. a large pill.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun A round mass of something, especially of chewed food in the mouth or alimentary canal.
  • noun A single, large dose of a drug, especially one in that form.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a small round soft mass (as of chewed food)
  • noun a large pill; used especially in veterinary medicine


from The American Heritage® Dictionary of the English Language, 4th Edition

[Medieval Latin bōlus, from Greek bōlos, lump of earth.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Late Latin bōlus ("clod of earth, lump"), from Ancient Greek βωλος (bōlos, "clod, lump").


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  • In reading messages I see the word bolus or something like that.

    Discussion Forum - TuDiabetes 2010

  • In gray matter, the labelled bolus is dispersed within three main compartments during image acquisition: the intravascular compartment; intracellular tissue space; and the extracellular tissue space.

    Naturejobs - All Jobs 2009

  • The weapon is called the bolus, and flying through the air it encircles the legs of the guana, bringing it to the earth.

    Memoirs of My Dead Life 1892

  • While it is possible children are more vulnerable in Africa because of malnutrition and the severity of diseases such as malaria, doctors say there is no clear reason why an injection of a large amount of fluid through a 15-minute drip - known as a bolus - would be more dangerous in Africa than in Europe.

    The Guardian World News Sarah Boseley 2011

  • When swallowing a bolus, which is a chunk of chewed food, it causes the esophagus to be stretched.

    CreationWiki - Recent changes [en] 2010

  • When swallowing a bolus, which is a chunk of chewed food, it causes the esophagus to be stretched.

    CreationWiki - Recent changes [en] 2010

  • When swallowing a bolus, which is a chunk of chewed food, it causes the esophagus to be stretched.

    CreationWiki - Recent changes [en] 2009

  • When swallowing a bolus, which is a chunk of chewed food, it causes the esophagus to be stretched.

    CreationWiki - Recent changes [en] 2009

  • After mastication, the food is worked by the tongue and cheeks into a saliva-soaked "bolus" and swallowed.

    Text Book of Biology, Part 1: Vertebrata 1906

  • Or, for dessert, a new bolus of legislation, all the parliamentary sewage flushed into one, a bill so heinous it will make it impossible even for Israel's best friends to defend Israel as a democracy, so extreme it will remove every remaining moral obstruction to branding Israel outright apartheid.

    Bradley Burston: In an Israel Reborn, a Glimpse of a New Israeli Bradley Burston 2011


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  • "Artefacts have also surfaced, making suggestions about how people lived in Nuvuk. Here, a body holds an ulu, a traditional knife used for taking blubber from whale carcasses; there, a grave gives up weights from a bolus which would have been used to hunt birds."

    - 'Bodies Point To Alaska's Past', Richard Black, BBC website 31 Dec 2007.

    January 1, 2008

  • Most often used by house officers to mean either a fluid bolus, which is a rapid infusion of some fluid, for instance saline, usu. made to improve blood pressure or replete lost water, or a drug bolus, which is a big, all-at-once starting dose of a drug that builds up blood levels quickly so that you can get clinical effects without waiting for several doses to go in.

    Can also be used as a verb: "Mrs Shalhoub's BP dipped, so I bolused her."

    January 26, 2008

  • Also used by type 1 diabetics who use insulin pumps, to describe a dose of insulin given to correct a high blood sugar or to account for the carbohydrates in a meal. May be used as a verb as noted by adoarns, e.g., "My blood sugar was a little high, so I bolused for that, and I'm having pizza for lunch, so I'll have to take another bolus pretty soon."

    June 20, 2008

  • “On the one hand, they said, the new president’s apparent enthusiasm for science, and the concomitant rise of ‘geek chic’ and ‘smart is the new cool’ memes, can only redound to the benefit of all scientists, particularly if the enthusiasm is followed by a bolus of new research funds.�?

    The New York Times, In ‘Geek Chic’ and Obama, New Hope for Lifting Women in Science , by Natalie Angier, January 19, 2009

    January 21, 2009

  • WORD: bolus

    EXAMPLE: ' Each candidate was to deliver two stool specimens to the Lovelace laboratory in Dixie cups, and days were going by and Conrad had been unable to egest even one, and the staff kept getting after him about it. Finally he managed to produce a single bolus, a mean hard little ball no more than an inch in diameter and shot through with some kind of seeds, whole seeds, undigested. Then he remembered. The first night in Albuquerque he had gone to a Mexican restaurant and eaten a lot of jalapeño peppers. They were jalapeño seeds. Even in the turd world this was a pretty miserable-looking objet. So Conrad tied a red ribbon around the goddamned thing, with a bow and all, and put it in the Dixie cup and delivered it to the lab. Curious about the ribbons that flopped out over the lip of the cup, the technicians all peered in. Conrad broke into his full cackle of mirth, much the way Wally might have. No one was swept up in the joke, however. The Lovelace staffers looked at the beribboned bolus, and then they looked at Conrad . . . as if he were a bug on the windshield of the pace car of medical progress. '

    1979. TOM WOLFE. The Right Stuff. "Chapter 4 -- The Lab Rat." (Page 75 ). Bantam Book edition (ISBN 0-553-27556-9).

    January 15, 2014