I know the meaning of the term "filter bubble" but I want to translate it and so I need to understand how the two words (filter and bubble) are connected to each other. Does the term mean "a bubble that act as a filter" or "a filter that act like a bubble". I need to know what the term is grammatically. More generally, how to understand it when two noun are coming in a row making a single term.
Sentence Example: Sites like Facebook are accused of creating "filter bubbles", the phenomenon of showing people things that they like or tend to agree with, and hiding those that they don't. (https://www.telegraph.co.uk/technology/0/fake-news-exactly-has-really-had-influence/)