1640s, in animal physiology, "act of preparing and expressing substances by glandular activity;" 1732 as "that which is secreted," from French sécrétion, from Latin secretionem (nominative secretio) "a dividing, separation," noun of action from past participle stem of secernere "to separate, set apart" (see secret (n.)).

"containing or resembling slime or mucus," 1640s (replacing mucilaginous), from Latin mucosus "slimy, mucous," from mucus (see mucus). Related: mucosity.

"mucous, slimy, covered with mucus," 1731, from Latin mucosus (see mucous). Related: Mucosity (1680s).

"produce, prepare, or elaborate by process of secretion," 1707 (implied in secreted), a back-formation from secretion. Related: Secretes; secreting; secretious.

"inflammation of the mucous membrane of the colon," 1860, from combining form of colon (n.2) + -itis "inflammation."

"inflammation of the mucous membrane of the pharynx," 1824, from stem of pharynx + -itis "inflammation."

"inflammation of the nose," especially the mucous membrane, 1829, medical Latin, from rhino- "nose" + -itis "inflammation."

"of or pertaining to secretion, having the function of secreting," 1690s; see secrete (v.1) + -ory.

early 15c., fleumi, "caused by an excess of phlegm (the bodily humor);" mid-15c., "sluggish;" from phlegm (q.v.) + -y (2). In reference to mucous or watery discharge by 1540s.

"mucous discharge from the nose," 1851, also rhinorrhoea, from rhino- "nose" + Greek rhoia "flow" (from PIE root *sreu- "to flow"). Attested in the 1840s in German, Italian, and French. Related: Rhinorhheal.