From Longman Dictionary of Contemporary Englishseal something ↔ in phrasal verbPREVENTto stop something that is inside something else from getting out Fry the meat quickly to seal in the juices. → seal→ See Verb table
Examples from the Corpus
seal in• A quiet rain has begun at the windows, sealing them in.• To improve the water resistant performance the flysheet seams can be sealed.• Any smooth flooring supplied unsealed should be sealed for use in a bathroom - instructions are supplied by the manufacturer.• Have her seal a straw in another bag in the same way you did the first one.• One such scheme would mix the plutonium with nasty but useless nuclear waste and seal it in blocks of glass.• Unfortunately, the burgeoning seal numbers in Boston Harbor bring the same problem seal abundance has brought elsewhere: human resentment.• Tomkins had planned to seal the transaction in mid - January after completing talks by the end of 1995.• He says the seals breath in the fumes and its really just like glue sniffing for them. 