The best replacement for deadbolt is deadlock.

The best alternatives to deadbolt are rated as following:
★★★★★  deadlock
★★★★  deadlatch
★★★  mortise lock
★★  spring bolt
★★  live bolt
★★  securesocial
★★  wraith
★★  deadbolt
★  double cylinder deadbolt
★  single cylinder
★  double cylinder
★  double deadbolt
★  ridgecrest
★  regular deadbolt
  single
  5 pin deadbolt
  single deadbolt

Your alternative for deadbolt is not listed? Suggest!
Speaking about deadbolt, one probably shouldn't forget about handle.

Other search terms related to deadbolt and their ratings are:
★★★★★ handle
door knob
You have in mind a companion for deadbolt and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of deadbolt in all years. Click on graph for more.
deadbolt
deadlock
deadlatch