"saliva," early 14c., from spit (v.1). Meaning "the very likeness" in modern use is attested from 1825 (as in spitting image, attested from 1887); compare French craché in same sense. Spit-curl (1831) was originally considered colloquial or vulgar. Military phrase spit and polish first recorded 1895.
spelling conventional in 15c.-17c. English to add emphasis to borrowed French nouns ending in stressed -on; also used to represent Italian -one, Spanish -ón; all from Latin -onem. Used in rare cases to form English words, such as spittoon, octoroon.
"offspring of a quadroon and a white," 1861, an irregular formation from Latin octo "eight" (see eight) + suffix abstracted from quadroon (in which the suffix actually is -oon). So called for having one-eighth Negro blood.
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Definitions of spittoon
a receptacle for spit (usually in a public place);