If you have done any significant amount of reading in English, you will notice that some verbs involving placing things inside other things begin with the prefix en-, while others begin with in-. There is no single rule for deciding which word gets which prefix. English borrowed the en- prefix from French, while in- comes from Old English, where it was originally borrowed from Latin. Some writers would consider tracing every word back to its origins a fascinating enterprise, while others would consider it a tedious chore. If you belong in the second category, you probably don’t have time to go digging though etymology to find out whether incase or encase is the correct spelling of that particular verb. Lucky for you, all you have to do is read this post.
Encase as verb:
Encase means to protect something within a covering. One might encase a valued instrument in a protective box, for instance, or an insect larva might encase itself in a chrysalis while it undergoes metamorphosis.
Use of encase:
Finland and Sweden hope to be the first countries in the world to be able to put the most dangerous high-level waste (HLW) into underground storage in the next decade, using a new technology to encase fuel rods and protect them from erosion. [The Japan Times]
Use of incase:
In case is a phrase that means to do something as a safeguard or precaution. This can also be used when someone else may have not done something (e.g., in case you haven’t…). This is always spelled as two words.
Encase or incase:
Encase is a verb that means to place in a protective shell or box. Incase is a spelling variant that has been outplaced by encase for almost 200 years. In case is a phrase that means to do something as a safeguard or precaution.