Entries linking to rheumy
late 14c., reume, "watery fluid or humid matter in the eyes, nose, or mouth" (including tears, saliva, mucous discharge from the nostrils), from Old French reume "a head-cold" (13c., Modern French rhume) and directly from Latin rheuma, reuma, from Greek rheuma "discharge from the body, flux; a stream, current, flood, a flowing," literally "that which flows," from rhein "to flow" (from PIE root *sreu- "to flow").
In old medicine it was conceived as draining from the higher to lower parts of the body and causing ailments if out of balance. Also from late 14c. as "a head-cold, catarrh." The -h- was restored in early Modern English.