The best replacement for tux is suit.

The best alternatives to tux are rated as following:
★★★★★  suit
★★★★  suit for prom
★★  black suit
★  clippy
  beastie
  black tux
  buying a suit
  mens warehouse
  buy suit
  grooms tux
  suit wedding

Your alternative for tux is not listed? Suggest!
Speaking about tux, one probably shouldn't forget about bow tie.

Other search terms related to tux and their ratings are:
★★★★★ bow tie
★★★★ cummerbund
★★★★ black shirt
★★★ long tie
★★★ pocket square
★★ red bow tie
★★ converse
★★ patent leather shoes
★★ brown vest
★★ skinny tie
★ chucks
white bow tie
ascot
You have in mind a companion for tux and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of tux in all years. Click on graph for more.
tux
suit
suit for prom