Umbo
Encyclopedia
Umbo may refer to:
- A shield bossShield bossA shield boss, or umbo, is a round, convex or conical piece of material at the centre of a shield. Shield bosses are usually made of thick metal but could also be made of wood. The boss was originally designed to deflect blows from the centre of round shields, though they also provided a place...
- umbo (mycology)Umbo (mycology)thumb|right|[[Cantharellula umbonata]] has an umbo.thumb|right|The cap of [[Psilocybe makarorae]] is acutely papillate.An umbo is a raised area in the center of a mushroom cap. Caps that possess this feature are called umbonate. Umbos that are sharply pointed are called acute, while those that are...
, at the top of some mushrooms - The Umbo of tympanic membraneUmbo of tympanic membraneThe umbo is the most depressed part of the tympanic membrane.-Depression:The manubrium of the malleus is firmly attached to the medial surface of the membrane as far as its center, which it draws toward the tympanic cavity; the lateral surface of the membrane is thus concave, and the most depressed...
- a part of the human body - Umbo is the (often somewhat protruding) part of a Bivalve shell which was formed when the animal was a juvenile
- The first year's growth of a seed scale on a pine coneConifer coneA cone is an organ on plants in the division Pinophyta that contains the reproductive structures. The familiar woody cone is the female cone, which produces seeds. The male cones, which produce pollen, are usually herbaceous and much less conspicuous even at full maturity...
, showing up as a protuberences at the end of the two-year-old scale - The tiny depression in the very center of the foveolaFoveolaThe foveola is located within a region called the macula, a yellowish, cone photo receptor filled portion of the human retina. The foveola is approximately 0.35 mm in diameter and lies in the center of the fovea and contains only cone cells, and a cone-shaped zone of Müller cells...
, and corresponds to the fovealFovealThe foveal system of the human eye is the only part of the retina that permits 100% visual acuity. The line-of-sight is a virtual line connecting the fovea with a fixation point in the outside world....
reflex.