Safehouse
A term of art in clandestine operations, which may be a physical house, an apartment, or even a concealed part of a park, with which the security authorities have not familiarity, and necessary meetings, training, and work cna take place. If a property, the person that bought or rented it has no other connection to the clandestine organization.
A very difficult decision can be the choice of whether to use other than the most secure, directional communications from a safehouse, or if there is too much danger of discovery. Interestingly, a pair of disposable cell phones may well carry out the function of a safehouse, without the dangers of meeting.
When there are meetings, the person who obtained the property may not be there, making the meeting deniable. A clandestine organization may have its own people followed to a meeting, to see if they are guiding the enemy to it, or just observing poor security.