- fontanelle
- One of several membranous intervals at the margins of the cranial bones in the infant. See cranial fontanelles. SYN: fonticulus. [Fr. dim. of fontaine, fountain, spring]- anterior f. [NA] a diamond-shaped membranous interval at the junction of the coronal, sagittal, and metopic sutures where the frontal angles of the parietal bones meet the two ununited halves of the frontal bone. SYN: bregmatic f., fonticulus anterior, frontal f..- anterolateral f. SYN: sphenoidal f..- Casser f. SYN: mastoid f..- cranial fontanelles [NA] the membranous intervals between the angles of the cranial bones in the infant; they include the midline anterior fontanel and posterior fontanel, and the paired sphenoidal fontanel and mastoid fontanel. SYN: fonticuli cranii.- mastoid f. [NA] the membranous interval on either side between the mastoid angle of the parietal bone, the petrous portion of the temporal bone, and the occipital bone. SYN: fonticulus mastoideus [NA], fonticulus posterolateralis, Casser f., posterolateral f..- posterior f. a triangular interval at the union of the lambdoid and sagittal sutures where the occipital angles of the parietal bones meet the occipital. SYN: fonticulus posterior, occipital f..- posterolateral f. SYN: mastoid f..- sagittal f. [NA] an occasional fontanel-like defect in the sagittal suture in the newborn. SYN: Gerdy f..- sphenoidal f. [NA] an irregularly shaped interval on either side where the frontal, sphenoidal angle of the parietal, squamous portion of the temporal and greater wing of the sphenoid meet. SYN: fonticulus sphenoidalis [NA], fonticulus anterolateralis, anterolateral f..
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n.an opening in the skull of a fetus or young infant due to incomplete ossification of the cranial bones and the resulting incomplete closure of the suture. The anterior fontanelle occurs where the coronal, frontal, and sagittal sutures meet; the posterior fontanelle occurs where the sagittal and lambdoidal sutures meet.* * *
fon·ta·nelle (fon″tə-nelґ) [Fr., dim. of fontaine spring, filter] fonticulus; see fonticuli cranii.
Medical dictionary. 2011.