to plant oneself in place: to take up a position and hold it, whether to wait, to appear before someone, or to stand one's ground
This verb always describes a person (or a creature, or even God) deliberately putting himself in a spot and staying there. The single picture underneath every use is someone taking up a position on purpose, not drifting into it.
Which English word fits depends on why the person plants himself. Sometimes it is simply to wait or watch from a chosen spot. Sometimes it is to appear before a king, a prophet, or God, presenting oneself to be seen, addressed, or judged. And sometimes it is to face an enemy and refuse to be moved, so that the word means to hold one's ground or withstand. These are not separate words but shades of one act: choosing a place and standing in it.
Because the act is always intentional, the verb often carries weight in a scene. To station yourself, to come and present yourself before the LORD, or to stand firm when armies advance are all charged moments, and the word marks the moment a person commits to a position.