Let is defined as to allow, to give the use of or leave someone or something.(verb)
See let in Webster's New World College Dictionary
Origin: ME leten < OE lætan, to leave behind, akin to Ger lassen < IE *lēd- < base *lēi-, to neglect, leave behind > late, L letum, death
Origin: ME letten < OE lettan, to hinder, lit., to make late (akin to Goth latjan, to delay) < base of læt, late
Origin: ME < MFr -el (< L -ellus) + -et, both dim. suffixes
See let in American Heritage Dictionary 4
verb let let, let·ting, lets verb, transitive
Origin: Middle English leten
Origin: , from Old English lǣtan; see lē- in Indo-European roots.
Origin: Middle English lette
Origin: , from letten, to hinder
Origin: , from Old English lettan; see lē- in Indo-European roots.
Origin: Middle English
Origin: , from Old French -elet, diminutive suff.
Origin: : -el (from Latin -ellus)
Origin: + -et, -et.
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