[] a substance, strip of material, etc. used to fill a crack so that air, liquid, etc. cannot get in or out密封垫（或带等）◆Make sure the seal is intact before closing the lid, or air will escape.在盖上盖子以前，确保密封垫完好无损，否则会漏气。 [] a piece of paper, metal, etc. that is placed across the opening of sth such as a letter, a box, etc. and which has to be broken before the letter or box can be opened封条 [] an official design or mark, stamped on a document to show that it is genuine and carries the authority of a particular person or organization印章；印记 [] a thing that makes sth definite表示确认的事物；保证◆The CEO has given the project his seal of approval.首席执行官已经正式批准了这个项目。●under ˈseal () () (about a document) that cannot be copied or made available to the public（文件）密封