English edit

Etymology edit

killer +‎ -ly

Adjective edit

killerly (comparative more killerly, superlative most killerly)

  1. (colloquial) Excellently.
    • 2011, Kelly McClymer, She's a Witch Girl[1]:
      After I'd outlined seven action steps to winning Nationals (practice like mortals, write a killer routine, fund-raise the application fee, get Coach Gertie to send in the forms, create team unity, get entire team focused on winning, perform a killerly perfect routine to wow the judges), I really got into the swing of the ugliest talking todo list.