foul as in; foul smell: nauseabond, infect, sale

foul as in; foul play: jeu deloyal (malveillance)

When your mattress grows too old to use, the upcoming purchase can be daunting, and sometimes you may try to prolong its inevitable discarding. Using mattress toppers or a protector is good to use to prolong your mattress life, but not when it's nearing its end. If your old mattress is already showing signs of aging and reducing your sleep quality, a mattress topper won't work a miracle. However, a mattress topper is an excellent mattress accessory upgrade when installed on a new mattress or a while after purchase. You may have the best mattress, but if it has lost its capabilities over time, there's not much you can do except discard it.

Prices of a Tempurpedic mattress pad ranges from $79 for a mattress protector to $299 for a mattress topper for times when a Tempurpedic mattress is not convenient.

The homophone of "foul" is "fowl."

Usually fair is given as the antonym for foul, as in foul play, foul weather, etc. There are many others, however, as there are several definitions of foul to begin with.