Let's Compare Mucosa and Serosa. 1  MUCOSA VS.  Mucosa. The mucous membranes (or mucosae or mucosas; singular mucosa) are linings of mostly endodermal origin, covered in epithelium, which are involved in absorption and secretion. mucosa \mucosa\ n.
Definition of dropper for English Language Learners. : a glass or plastic tube that is used to measure out liquids by drops.
In an effort so standardize the dropper, the United States Pharmacopoeia/National Formulary (USP/NF) has recognized an official medicine dropper which is designed to deliver 1 ml of water in 20 drops with an allowable 10% deviation (Â± 2 drops).