word-forming element expressing state or condition, in medical terminology denoting "a state of disease," from Latin -osis and directly from Greek -osis, formed from the aorist of verbs ending in -o. It corresponds to Latin -atio.
1959 as a shortening of monophonic in reference to recordings; earlier used among printers for "monotype machine" (c. 1925) and generally for monochrome (motorcar, etc.), 1940s. From 1964 as short for mononucleosis.
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Harper, D. (n.d.). Etymology of mononucleosis. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/mononucleosis
D. Harper. “Etymology of mononucleosis.” Online Etymology Dictionary. https://www.etymonline.com/word/mononucleosis (accessed $(datetime)).
Definitions of mononucleosis
an acute disease characterized by fever and swollen lymph nodes and an abnormal increase of mononuclear leucocytes or monocytes in the bloodstream; not highly contagious; some believe it can be transmitted by kissing;