1. To exchange or swap someone (for someone else). A noun or pronoun can be used between "switch" and "out." They switched the star forward out after he sprained his ankle. This is the third time this year that they've switched out the regional manager for someone new.
2. To exchange some piece, part, or component for a new or different one. A noun or pronoun can be used between "switch" and "out." You can switch out the various parts of the model airplane to create your own customized vehicle. We'll need to switch the fuse out before the lights will come back on.
switch something out
to remove something from an electrical circuit to turn it off. Please switch the light out. I switched out the light.