A hypochondriac someone who constantly worries about his health. Although there may be nothing really wrong with him, he always imagines that there is something seriously wrong. A hypochondriac is obsessed about his health. He has imaginary ailments. Such people give doctors a tough time.
Examples: “Luckily, we don’t have a hypochondriac in our family.”
A cyberchondriac is someone who gets all his medical information from the Internet or reads about the various diseases going around and imagines that he has them too.
Example: “I am told that my boss’ wife is a cyberchondriac.”