The word(s) "seal" appears 18 time(s) in 18 verse(s) in Quran in Muhammad Habib Shakir translation.

(11) On that day We will set a seal upon their mouths, and their hands shall speak to Us, and their feet shall bear witness of what they earned.

(12) Those who dispute concerning the communications of Allah without any authority that He has given them; greatly hated is it by Allah and by-those who believe. Thus does Allah set a seal over the heart of every proud, haughty one.

(13) Or do they say: He has forged a lie against Allah? But if Allah pleased, He would seal your heart; and Allah will blot out the falsehood and confirm the truth with His words; surely He is Cognizant of what is in the breasts.

(14) Have you then considered him who takes his low desire for his god, and Allah has made him err having knowledge and has set a seal upon his ear and his heart and put a covering upon his eye. Who can then guide him after Allah? Will you not then be mindful?

(15) And there are those of them who seek to listen to you, until when they go forth from you, they say to those who have been given the knowledge: What was it that he said just now? These are they upon whose hearts Allah has set a seal and they follow their low desires.

(16) That is because they believe, then disbelieve, so a seal is set upon their hearts so that they do not understand.

(17) They are made to quaff of a pure drink that is sealed (to others).

(18) The sealing of it is (with) musk; and for that let the aspirers aspire.