ṣāvāʾ צָבָא ‘to serve’ (Hebrew)

Etymology^?: a primitive root

ṣāvāʾ v
1) to go forth, wage war, fight, serve
 1a) (Qal)
  1a1) to wage war, fight, go forth to war
  1a2) to serve (at sacred tent)
 1b) (Hiphil) to cause to go forth, muster