The most common and most likely answer to this crossword clue is the 11 letter word UNDERGROUND
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More clues leading to the result UNDERGROUND
- Revolutionary reporting to base
- Resistance movement not fully crushed
- Tube not fine enough
- Tube not sufficiently fine?
- Related to subversive activities of a French revolutionary uprising with foundation’s support
- A Parisian upset revolutionary foundation characterised by avant-gardism
- Resistance insufficiently worn down?
Buddy explains!

The straight part
We know that "Related to subversive activities" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case related to subversive activities = underground.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does UNDERGROUND mean?
UNDERGROUND noun- An underground railway, especially for mass transit of people in urban areas.
- A train that runs on such an underground railway.
- A rapid transit system, regardless of the elevation of its right of way.
- An underground walkway, tunnel for pedestrians (called pedestrian underpass in US).
- An underground route for pipes, sewers, etc.
- Regions beneath the surface of the earth, both natural (eg. caves) and man-made (eg. mines).
- (with definite article) A movement or organisation of people who resist political convention.
- (with definite article) A movement or organisation of people who resist artistic convention.
- To route electricity distribution cables underground
- Below the ground; below the surface of the Earth.
- Hidden, furtive, secretive.
- Outside the mainstream, especially unofficial and hidden from the authorities.
- Below the ground.
- Secretly.