The best replacement for mug is cup.

The best alternatives to mug are rated as following:
★★★★★  cup
★★★  kisser
★★  a&w
★★  tumbler
★  stein
  paper cup
  bowl
  barq's
  scuttle
  jug
  rob
  seidel stein
  slushy magic
  tankard
  coffee cup
  us mug
  ceramic mug
  classic mug

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

Other search terms related to mug and their ratings are:
★★★★★ infuser
★★ tea infuser
mug
You have in mind a companion for mug and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of mug in all years. Click on graph for more.
mug
cup
kisser