Although Marion Wormer, in Animal House, famously says “vegetables are sensual, people are sensuous,” her intention is not quite right. Sensual means relating to pleasure or the physical (especially sexual) sense; sensuous, a more neutral word, means relating to or involving or arousing any of the five common senses. A person’s excitement can be more sensuous than intellectual, but that does not make the person sensuous. And vegetables may fulfill sensual pleasure but tend not to be sensual themselves.
Adhere to the two words’ strict senses, even if sensuous is often mistaken for sensual and may someday lose its distinct definition altogether. But if such development were to become standard, sensuous should be abandoned for the more accurate and visceral sensual, and sensory, the most technical of the three words, should be used when meaning relating to the physical senses.