The prefix intra means within, and is the opposite of extra which I discussed in a previous blog entry.
Intra should not be confused with inter which means between or among two or more entities. I will discuss this is a future blog article.
Here are some words using intra:
intranet (noun) a local or restricted communications networks, especially a web-based service inside an organisation.
intramural - (adjective) - situated or done within the walls of an institution.
intravenous (adjective) - within or into a vein. Some drugs are taken intravenously, meaning they are injected.