The best replacement for affair is relationship.

The best alternatives to affair are rated as following:
★★★★★  relationship
★★★★  fling
★★★★  affaire
★★★  friendship
★★★  cheating
★★★  one night stand
★★★  divorce
★★  prostitute
★★  midlife crisis
★  physical affair
★  friends with benefits
★  affair
  mistress
  fwb
  emotional affair
  just friends
  departed
  adultery
  platonic friendship
  romance
  an affair to remember
  no other woman
  infidelity
  temptation of wife

Your alternative for affair is not listed? Suggest!
Speaking about affair, one probably shouldn't forget about married woman.

Other search terms related to affair and their ratings are:
★★★★★ married woman
★★★★★ guilt
★★★★ flair
★ senator
You have in mind a companion for affair and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of affair in all years. Click on graph for more.
affair
relationship
fling