- A general term for cavity or chamber which may have specific meaning in reference certain organs or sites in the body. The antrum of the stomach (gastric antrum) is a portion before the outlet which is lined by mucosa which does not produce acid. The paranasal sinuses can be referred to as the frontal antrum, ethmoid antrum, and maxillary antrum.
* * *1. Any nearly closed cavity, particularly one with bony walls. 2. SYN: pyloric a.. [L. fr. G. antron, a cave]- cardiac a. a dilation that occasionally occurs in the abdominal part of esophagus. SEE ALSO: abdominal part of esophagus. SYN: a. cardiacum, forestomach.- a. cardiacum SYN: cardiac a..- antra ethmoidalia SYN: ethmoid cells, under cell.- mastoid a. [TA] a cavity in the petrous portion of the temporal bone, communicating posteriorly with the mastoid cells and anteriorly with the epitympanic recess of the middle ear via the aperture of the mastoid a.. SYN: a. mastoideum [TA], tympanic a., Valsalva a..- a. mastoideum [TA] SYN: mastoid a..- pyloric a. [TA] the initial portion of the pyloric part of the stomach, which may temporarily become partially or completely shut off from the remainder of the stomach during digestion by peristaltic contraction of the prepyloric “sphincter”; it is sometimes demarcated from the second part of the pyloric part of the stomach (pyloric canal) by a slight groove. SYN: a. pyloricum [TA], a. (2) [TA], lesser cul-de-sac.- a. pyloricum [TA] SYN: pyloric a..
* * *an·trum 'an-trəm n, pl an·tra -trə a cavity within a bone (as the maxilla) or hollow organ (as the stomach)
* * *n.1. a cavity, especially a cavity in a bone. The mastoid (or tympanic) antrum is the space connecting the air cells of the mastoid process with the chamber of the inner ear.
* * *an·trum (anґtrəm) pl. anґtra, antrums [L., from Gr. antron cave] a cavity or chamber, such as one within a bone or organ. antral adj
Medical dictionary. 2011.