Origin and history of tithe

"a tenth, a tenth part" (originally of goods or produce) due as support of the clergy, c. 1200, from Old English teogoþa (Anglian), teoþa (West Saxon) "tenth," from Proto-Germanic *tegunthan (from PIE *dekmto-, from PIE root *dekm- "ten"). It was retained in the ecclesiastical sense while the form was replaced in ordinal use by tenth. In early Middle English tithe also was a numeral, "tenth."

Middle English tithen, from Old English teoþian "to pay one-tenth," especially "give one-tenth of goods or income to the church as a religious duty;" from the root of tithe (n.). As "to impose a payment of a tenth; subject to tithes or payment of a tithe," late 14c. Related: Tithed; tithing.

In Middle English, when the sense of "one-tenth" was felt, it also could mean "kill one in 10, decimate" (late 14c.). A tithing was "a one-tenth part," from Old English teoðung, especially of goods and property. It also was an old administrative division equal to one-tenth of a hundred, or a group of 10 households (late 12c.). A tithing-man was thus an under-constable; in early New England it was the name of a town officer in charge of public morals.