The best replacement for mortar is grout.

The best alternatives to mortar are rated as following:
★★★★★  grout
★★★★★  cement
★★★★  concrete
★★★  mastic
★★  thinset
★  online
★  wizard tower
★  pestle
★  sand mix
★  e-business
★  concrete mix
★  howitzer
  ebusiness marketing
  cannon
  e-commerce
  archer tower
  online business
  artillery
  dry stack
  click and mortar
  adhesive
  online shopping
  unmodified mortar
  online sales
  type s mortar
  ebusiness
  mortar
  ecommerce
  tile adhesive
  portland cement
  type n mortar
  hidden tesla
  brick

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

Other search terms related to mortar and their ratings are:
★★★★★ pestle
★★ lime mix
★ pva
★ pavers
★ bricks
★ stone
type s hydrated lime
You have in mind a companion for mortar and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of mortar in all years. Click on graph for more.
mortar
grout
cement