To retire
recede, withdraw, draw back, retrograde, back out, retract, leave, go, depart, recoil, shrink, quail, run, reel, start back, pull back, reverse, seclude oneself, keep aloof, keep apart, hide, separate from, regress, resign, relinquish, lay down, hand over, sequester oneself, retrocede, backtrack, back off, back down, chicken out*.
Antonyms stay*, continue, advance.
In battle, to execute a forced retirement
evacuate, abandon, leave, withdraw, back out, vacate the position, retire, remove, pull out, march out, disengage, turn back, fall back, draw back, move back, give ground, move behind, beat a retreat, back down, escape, decamp, fly, run away, turn tail, be routed, give way, flee, flee in disorder, execute a strategic withdrawal, shorten one's lines, avoid, evade, elude.
Antonyms attack*, progress, drive forward.