If a person or an object is encased in something, they are completely covered or surrounded by it. When nuclear fuel is manufactured it is encased in metal cans These weapons also had a heavy brass guard which encased almost the whole hand The original plan was to encase a small amount of a radioactive substance in a protective steel container. to cover or surround something completely encase sth in sth
A stamp inserted into a small coin-size case with a transparent front or back Such stamps were circulated as legal coins during periods when coins were scarce