let vs protest

let

verb
  • To give, grant, or assign, as a work, privilege, or contract; often with out. 

  • Used to introduce a first or third person imperative verb construction. 

  • To cause (+ bare infinitive). 

  • To allow the release of (a fluid). 

  • To allow possession of (a property etc.) in exchange for rent. 

  • To allow to be or do without interference; to not disturb or meddle with; to leave (someone or something) alone. 

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

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

  • An obstacle or hindrance. 

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

protest

verb
  • To object to. 

  • to make a solemn written declaration, in due form, on behalf of the holder, against all parties liable for any loss or damage to be sustained by non-acceptance or non-payment of (a bill or note). This should be made by a notary public, whose seal it is the usual practice to affix. 

  • To affirm (something). 

  • To make a strong objection. 

  • To call as a witness in affirming or denying, or to prove an affirmation; to appeal to. 

noun
  • The noting by a notary public of an unpaid or unaccepted bill. 

  • A written declaration, usually by the master of a ship, stating the circumstances attending loss or damage of ship or cargo, etc. 

  • A formal objection, especially one by a group. 

  • A collective gesture of disapproval; a demonstration. 

How often have the words let and protest occurred in a corpus of books? (source: Google Ngram Viewer )