let

verb

1. (transitive)To allow to, not to prevent (+ infinitive, but usually without to).

   “After he knocked for hours, I decided to let him come in.”

   “Pharaoh said, I will let you go.”

   “If your name be Horatio, as I am let to know it is[…]”

   “He could not be let die of thirst there alone in the dark.”

   “The dirty secret of the internet is that all this distraction and interruption is immensely profitable. Web companies like to boast about […], or offering services that let you "stay up to date with what your friends are doing",[…]and so on. But the real way to build a successful online business is to be better than your rivals at undermining people's control of their own attention.”

2. (transitive)To allow to be or do without interference; to not disturb or meddle with; to leave alone.

   “Let me be!”

   “Yet neither spinnes nor cardes, ne cares nor frets, / But to her mother Nature all her care she lets.”

3. (transitive)To allow the release of (a fluid).

   “The physicians let about a pint of his blood, but to no avail.”

4. (British, transitive)To allow possession of (a property etc.) in exchange for rent.

   “I decided to let the farmhouse to a couple while I was working abroad.”

   ““My dear Mr. Bennet,” said his lady to him one day, “have you heard that Netherfield Park is let at last?” Mr. Bennet replied that he had not. “But it is,” returned she; “for Mrs. Long has just been here, and she told me all about it.””

   “Trailers for sale or rent, rooms to let, fifty cents.”

5. (transitive)To give, grant, or assign, as a work, privilege, or contract; often with out.

   “to let the building of a bridge;  to let out the lathing and the plastering”

6. (auxiliary, transitive)Used to introduce a first or third person imperative verb construction.

   “Let's put on a show!”

   “Let us have a moment of silence.”

   “Let me just give you the phone number.”

   “Let P be the point where AB and OX intersect.”

   “"Let there be no doubt: I saw you boyfriend with another girl" "Let him. I don't care anymore".”

7. (transitive)To cause (+ bare infinitive).

   “Can you let me know what time you'll be arriving?”

   “Soo within a whyle kynge Pellinore cam with a grete hoost and salewed the peple and the kyng and ther was grete ioye made on euery syde. Thenne the kyng lete serche how moche people of his party ther was slayne. And ther were founde but lytel past two honderd men slayne and viij knyȝtes of the table round in their pauelions.”

   “Time's sea hath been five years at its slow ebb, / Long hours have to and fro let creep the sand[…].”

   “What right had the unclean and stupid farmer, whose farm abutted on this sky water, whose shores he has ruthlessly laid bare, to give his name to it? ... Rather let it be named from the fishes that swim in it, the wild fowl or quadrupeds which frequent it, the wild flowers which grow by its shores, or some wild man or child the thread of whose history is interwoven with its own...”

8. (archaic)To hinder, prevent, impede, hamper, cumber; to obstruct (someone or something).

   “He who now letteth will let, until he be taken out of the way.”

   “Sir King, mine ancient wound is hardly whole, / And lets me from the saddle; […]”

9. (obsolete)To prevent someone from doing something; also to prevent something from happening.

   “& there was syr Mordred redy awaytynge vpon his londage to lette his owne fader to lāde vp the lande that he was kyng ouer. "And there was Sir Mordred ready awaiting upon his landing, to let his own father to land upon the land that he was king over."”

   “And as they went on their waye, they cam unto a certayne water, and the gelded man sayde: Se here is water, what shall lett me to be baptised?”

10. (obsolete)To tarry or delay.

    “And for that strake I would not let, / Another upon him soon I set, […]”

noun

1. The allowing of possession of a property etc. in exchange for rent.

   “Then he says “You would call it a Good Let, Madam?” “O certainly a Good Let sir.””

2. (obsolete)An obstacle or hindrance.

   “without let or hindrance”

   “[E]ver conſider vvhether our doings be to the let of our ſalvation or not.”

   “And Cadmus saw his campanie make tarience in that sort / He marveld what should be their let, and went to seeke them out.”

   “Paulus Emilius going to the glorious expedition of Macedon, advertised the people of Rome during his absence not to speake of his actions: For the licence of judgements is an especiall let in great affaires.”

3. The hindrance caused by the net during serve, only if the ball falls legally.