- 1. A straight line connecting two opposite points on the surface of a more or less spherical or cylindrical body, or at the boundary of an opening or foramen, passing through the center of such body or opening. 2. The distance measured along such a line. [G. diametros, fr. dia, through, + metron, measure]- diagonal conjugate d. SYN: diagonal conjugate.- d. obliqua [TA] SYN: oblique d..- oblique d. [TA] a measurement across the pelvic inlet from the sacroiliac joint of one side to the opposite iliopectineal eminence. SYN: d. obliqua [TA].- obstetric conjugate d. SYN: true conjugate.- occipitofrontal d. the d. of the fetal head from the external occipital protuberance to the most prominent point of the frontal bone in the midline.- occipitomental d. the d. of the fetal head from the external occipital protuberance to the midpoint of the chin.- posterior sagittal d. distance from the sacrococcygeal junction to the middle of an imaginary line running between the left and right ischial tuberosities.- suboccipitobregmatic d. the d. of the fetal head from the lowest posterior point of the occipital bone to the center of the anterior fontanelle.- total end- diastolic d. (TEDD) cross sectional d. of the left ventricle including the septum and posterior wall thicknesses in diastole.- total end- systolic d. (TESD) cross sectional d. of the left ventricle including the septum and posterior wall thicknesses in systole.- trachelobregmatic d. the d. of the fetal head from the middle of the anterior fontanelle to the neck.- d. transversa [TA] SYN: transverse d..- transverse d. [TA] the transverse d. of the pelvic inlet, measured between the terminal lines. SYN: d. transversa [TA].
* * *di·am·e·ter dī-'am-ət-ər n1) a unit of magnification for an optical instrument equal to the number of times the linear dimensions of an object are apparently increased <a microscope magnifying 60 \diameters>2) one of the maximal breadths of a part of the body <the transverse \diameter of the inlet of the pelvis>
* * *di·am·e·ter (di-amґə-tər) the length of a straight line passing through the center of a circle and connecting opposite points on its circumference; hence the distance between two specified opposite points on the periphery of a structure such as the cranium or pelvis. Symbol d.
Medical dictionary. 2011.