Pretty much the title is the question. Lets take the massive blackhole of our milky way does this black hole orbit something?
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$\begingroup$ I think that "Does Sgr A* orbit something?" could be an interesting Astronomy SE question. You could start by pointing out that the Sun orbits the solar system barycenter, which sometimes is outside the Sun, and that the solar system orbits the center of our galaxy, and just ask if that whole thing orbits anything else. This could have a clear and definitive answer. $\endgroup$– uhohJan 22 at 1:00
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$\begingroup$ Based on that answer, you could consider asking a second question about "everything". $\endgroup$– uhohJan 22 at 1:00
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1$\begingroup$ @uhoh, I think Astronomy had a recent question on 'what is everything orbiting?' $\endgroup$– GremlinWrangerJan 22 at 1:12
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There is a balance to be had between relative velocity, mass and distance of objects. Below a certain threshold objects will tend to orbit each other. Above it they won't.
As an example some objects have sufficient velocity to pass through the Solar System without orbiting the Sun. Similarly some objects acquire sufficient velocity to be ejected from the Milky way entirely never to return.
As for galaxies themselves, I believe that the distances are so vast and the relative velocities so high that large galaxies do not strictly orbit one another. Although there is gravitational interaction the universe at the very largest scales appears more like a web like structure with vast filaments and voids.
A word of caution here. The rotation of stars in galaxies do not appear to agree with our existing laws of gravity. Dark matter has been proposed as one solution to this discrepancy, but it is unclear exactly what this might consist of...
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1$\begingroup$ I would add that although ojects don't strictly orbit another objects in general, the mass of every objects in space has an influence on other objects. So objects tend to move in complicated trajectories according to the mass distribution around them. Larger scale structures such as galaxies superclusters show attractive regions towards which inner clusters are flowing to (see en.wikipedia.org/wiki/Great_Attractor). $\endgroup$– KrafpyJan 19 at 18:17