Ideographic: Steam 烝 provides the meaning and soundRadical:

meaning for zhēng:

  • - to evaporate
  • - (of cooking) to steam
  • - torch made from hemp stalks or bamboo (old)
  • - finely chopped firewood (old)to evaporate
  • - evaporationsteamvapor
  • - steam(of a vapor etc) to rise
  • - to hang in the airbecoming more prosperous with each passing day