The best replacement for null is alternative hypothesis.

The best alternatives to null are rated as following:
★★★★★  alternative hypothesis
★★★  not null
★★★  empty
★★★  0
★★★  blank
★★  nil
★★  nullptr
★★  not an object
★★  empty string
★★  undefined
★  zero
★  empty string sql
★  void
★  empty string java
★  research hypothesis
★  null
  0 c++
  dbnull
  empty php
  empty sql
  nothing
  undefined check javascript
  nul
  null php
  undefined javascript
  false
  is null
  none
  alternate hypothesis
  empty sql server
  null sql server

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

Other search terms related to null and their ratings are:
★★★★★ default
★★★ case sql server
★★ null null
★ empty string
You have in mind a companion for null and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of null in all years. Click on graph for more.
null
alternative hypothesis
not null