The best replacement for mousse is gel.

The best alternatives to mousse are rated as following:
★★★★★  gel
★★★  hairspray
★★★  pomade
★★  pudding
★★  hair gel
★  hair spray
★  pate
★  bavarian cream
★  foundation
★  liquid foundation
★  bavarois
  whipped foundation
  mousseline
  bavarian
  curl cream
  custard
  ganache
  styling cream
  leave in conditioner
  leave-in conditioner
  tubliss
  setting lotion
  ressort

Your alternative for mousse is not listed? Suggest!
Speaking about mousse, one probably shouldn't forget about jello and cool whip.

Other search terms related to mousse and their ratings are:
★★★★★ jello and cool whip
★★★★★ dry hair
You have in mind a companion for mousse and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of mousse in all years. Click on graph for more.
mousse
gel
hairspray