Wiktionary
n. A term used to cover a broad category of functions rather than a single specific item
Wikipedia
An umbrella term is a word or phrase that covers a broad interval or set of functions or items that all fall under a single common category. For example, cryptology is an umbrella term that encompasses cryptography and cryptanalysis, among other fields. Similarly, an umbrella organization is a central and coordinating body representing a number of smaller, separate bodies.
The closely related blanket term is a word or phrase that is used to describe multiple groups of related things. The degree of relation may vary or have a minimal relationship, but blanket terms often trade specificity for ease of use. In other words, a blanket term, by itself, gives little detail about the things that it describes or the relationships between them, but it is easy to say and remember. Blanket terms may originate as slang but eventually become integrated into the general vocabulary.
Usage examples of "umbrella term".
A kind of vague umbrella term for those sympathetic to the underground, but not followers of any more specific political movement or philosophy.
Asex was really nothing but an umbrella term for a broad group of philosophies, styles of dress, cosmetic-surgical changes, and deep-biological alterations.
MKULTRA is an umbrella term for the Company's mind control experiments.