early 15c., "watery," later "of or pertaining to serum" (16c.), from French séreux (16c.) and directly from Latin serosus, from serum "watery fluid, whey" (see serum). Related: Serosity.
a serous exudate
sermonette
sermonize
serology
serotine
serotonin
serous
serpent
serpentine
serrate
serrated
serration
