Word Of The Day

Dorland's Word of the Day is a great way to broaden your knowledge of medical terminology. With a new and interesting term brought to you from the 32nd edition of Dorland's Illustrated Medical Dictionary each day, it's an easy and fun way to increase your medical vocabulary!

You can view a new word on this website each day.

Today's Word

terminal saccular period

the period or phase of prenatal lung development lasting, in different parts of the lungs, from the twenty-sixth week or later until near term, and followed by the alveolar period. Walls of the air spaces become thinner and the spaces divide into alveolar saccules with adjacent capillaries; type I and type II alveolar cells begin functioning and surfactant is secreted. Called also terminal saccular phase.

Word of the Day Archive

microchimerism

the presence in an individual of small numbers of cells or small amounts of DNA derived from another genetically distinct individual, as of donor cells in a graft recipient or of cells transferred between mother and fetus during pregnancy.

abembryonic pole

the pole of the blastocyst opposite the embryonic pole, that is, further away from the embryoblast; this location is the site of trypsinlike activity that is responsible for the shedding of the zona pellucida.

Nosema connori

a species of protozoa that causes corneal and disseminated infections in humans.

pseudoglandular period

the period or phase of prenatal lung development lasting from about the sixth to the sixteenth week, and followed by the canalicular period. Repeated branching of bronchi and bronchioles takes place to form primordial conductive airways, and the lungs resemble exocrine glands. Fetuses delivered during this phase are not viable because the lungs are not capable of respiration until the twenty-fourth to twenty-sixth week. Called also pseudoglandular phase.

redundancy

the presence of multiple copies of a gene in a genome, or of the same or similar DNA sequences.

alveolar gas exchange

the passage of oxygen and carbon dioxide in opposite directions across the alveolocapillary membrane.

isthmus of gastric gland

the part of a gastric gland immediately adjacent to the opening into the gastric pit.