Category: O

  • Obsolescent

    Almost obsolete, used for non-functional parts of organs.  

  • Obreniform

    Kidney-shaped with the point of attachment at the rounded side not in the sinus.  

  • Obpyriform

    Obpyriform

    (Of a 3-dimensional shape) like an inverted pear, i.e. with the broadest part proximal.  

  • Obovoid

    Obovoid

    Egg-shaped (3-dimensional), with the broadest part towards the apex. Ovoid, but with the attachment at the short end.  

  • Obovate

    Obovate

    Egg-shaped (2-dimensional) with the broadest part near the apex. Similar to ovate but larger toward the tip of the leaf. Reverse ovate, with the broadest part above. Egg-shaped, with the broader end at the tip. Paddle shaped; narrowest at the bottom. Ovate but with the close part toward the attachment. Of leaves, oval but broader…

  • Oblong

    Oblong

    (Of a plane shape) longer than broad, with the margins parallel for most of their length. (There is confusion about this term: many authors seem to regard it as including rounded ends; about as many others (including the authoritative 1962 Taxon article on plane shapes) only mean the term to include ‘quite a bit longer…

  • Obloid

    Obloid

    A 3-dimensional shape with short parallel sides and rounded ends, as if composed of two hemispheres linked together by a short cylinder [unusual term].  

  • Oblique

    (In leaves) when the two sides of the leaf are unequal near the base; (In an ovary) when the ovary is at an angle to the symmetric plane. Asymmetrical; unequal-sided. Applied to organs having unequal sides. Lying at an angel.  

  • Oblate

    Oblate

    (Of a globose shape) flattened at the poles, like an orange.  

  • Oblanceolate

    Oblanceolate

    Narrowly obovate and tapering to a point at the apex. Reverse lanceolate, widest above the middle of the blade. Lance-shaped; long and narrow, with the fatter end at the tip. Of leaves, lance-shaped but broader toward the apex. As in the lanceolate leaf, but the petiole attached at the narrow end. Lance-shaped, with the point…