Is there an antonym for the verb besiege? asked for an “opposite” for the word besiege, with answers like occupy, barricade, where the person doing the barricading is inside the barrier, defending his position from outsiders. In a siege, the person doing the barricading is outside, cutting off those inside.
The antonym of besiege is relieve: a siege is lifted.
Barricade is not an antonym of besiege, even though the sense is “opposite”; it could be a synonym of besiege if the siege is realised by a barricade. However occupy isn't a synonym of besiege as the meanings are very different. It's also not the antonym of besiege.
So the relationship between besiege and barricade/occupy is not one of synonyms or antonyms. Is there a -nym word — or indeed any other word — which describes this opposite direction of action (for want of a better term)?
Since I've used the SWR tag, an example sentence would be “Occupy is an _____________ of besiege.”
Note: the concept of siege can “work both ways”, with a siege mentality applying to those barricade themselves in. I mention that here only to show that occupy only “works one way”, in a different “direction” to besiege.