What is the meaning of the word "mount"?

Definitions:

a mounting consisting of a piece of metal (as in a ring or other jewelry) that holds a gem in place noun
- the diamond was in a plain gold mount
attach to a support verb
- They mounted the aerator on a floating
fix onto a backing, setting, or support verb
- mount slides for macroscopic analysis
get up on the back of verb
- mount a horse
prepare and supply with the necessary equipment for execution or performance verb
- mount a theater production
put up or launch verb
- mount a campaign against pornography