If you're thinking of the physical object:
* Unmoor: This is the most direct opposite, meaning to release an anchor from its hold.
* Drift: This means to move aimlessly, lacking a fixed position.
* Float: This means to stay on the surface of water, not grounded.
If you're thinking of the metaphorical sense of being anchored:
* Untethered: This means to be free from restraint or restrictions.
* Free: This means to be without limitations or constraints.
* Volatile: This means to be unpredictable and prone to sudden change.
* Transient: This means to be temporary or fleeting.
Other possibilities:
* Release: This could be a general term for letting go of something that anchors you.
* Move: This could mean to shift your position physically or metaphorically.
* Change: This could refer to a shift in your perspective or way of life.
To give you the most accurate opposite, please provide more context about how you're using the word "anchor".