Crossword Dictionary

let

let, allow, permit - v 
make it possible through a specific action or lack of action for something to happen; "This permits the water to rush in"; "This sealed door won't allow the water come into the basement"; "This will permit the rain to run off" 

wordplays

synonyms

authorize, commission, empower, license (also licence), approve, endorse (also indorse), sanction

in a sentence

my parents would not let me drive until I had a job and could pay for my own gas

the low gravity on the moon lets you make enormous leaps and jumps

they let their kids get away with murder

merriam-webster

etymology

Old English lætan (Northumbrian leta) "to allow; to leave behind, depart from; leave undone; bequeath," also "to rent, put to rent or hire" (class VII strong verb; past tense let, leort, past participle gelæten), from Proto-Germanic *letan (source also of Old Saxon latan, Old Frisian leta, Dutch laten, Old High German lazan, German lassen, Gothic letan "to leave, let"), from PIE *led-, extended form of root *‌‌lÄ“- "to let go, slacken." If that derivation is correct, the etymological sense would be "let go through weariness, neglect."

etymonline