Glossary

Category: O

  • Onion

    Onion

    A labour union brings together many different individuals; a garden onion has many tightly bound layers. This connection explains why both words—union and onion—derive from the Late Latin unio, meaning oneness or unity, which in turn arose from the Latin unus, meaning one. The earliest English spellings of the bulb’s name—unyonn back in the fourteenth…

  • One-arm

    One-arm refers not to a careless sausage maker, but to a kind of cheap restaurant, in vogue in the first two decades of the twentieth century, where a patron ate his meal from a seat that had one arm wide enough to support his tray.  

  • Omnivorous

    The Latin word vorare, meaning to devour, has been compounded with other Latin words to form omnivorous (all-devouring), carnivorous (flesh-devouring), and herbivorous (plant-devouring). All these words entered English in the mid sixteenth century as zoological terms; much more recently batrachivorous was adopted for application to people in nations such as France who eat grenouille, in…

  • Omelette

    Omelette

    Strange as it might seem, the word omelette is related to both the word laminate and the word enamel, but is not related to the similar sounding amulet, a charm that wards off evil spirits. Omelette ultimately goes back to the Latin word lamina, meaning a plate of metal. Lamina gave rise to a diminutive…

  • Offal

    When you set about to butcher a chicken, the first thing you do is chop off its legs and head; these severed items are as unimportant to you as they were important to the bird, and thus you sweep them to the edge of the table where they fall onto the floor. It is this…

  • Oxidizing agent (oxidant)

    The acceptor of electrons in an oxidation-reduction reaction. The oxidant is reduced by the end of the chemical reaction. That is, the oxidizing agent is the entity that seeks and accepts electrons. Electron acceptance is, by definition, reduction.  

  • Oxidation-reduction reaction

    A chemical reaction in which electrons are transferred from a donor to an acceptor molecule or atom. A chemical interaction in which one substance is oxidized and loses electrons, and thus is increased in positive valence, while another substance gains an equal number of electrons by being reduced and thus is decreased in positive valence.…

  • Overwinding

    Positive supercoiling. Winding which applies further tension in the direction of winding of the two strands about each other in the duplex.  

  • Outcrossing

    The transfer of a given gene or genes (e.g., one synthesized by man and inserted into a plant via genetic engineering) from a domesticated organism (e.g., crop plant) to wild type (relative of plant).  

  • Osteoinductive factor (OIF)

    A protein that induces the growth of both cartilage-forming cells and bone-forming cells (e.g., after a bone has been broken). When applied in the presence of transforming growth factor-beta, type 2 (another protein), osteoinductive factor first causes connective tissue cells to grow together to form a matrix of cartilage (e.g., across the bone break), then…