A morbiliform rash is a rash that resembles the type of rash
that appears during a measles infection. Literally, morbiliform
means "measles-like." It is a maculopapular rash that usually
distributes symmetrically across the body. Maculopapular means that
the rash has both elements of a macule and a papule. Saying it is a
macule means that it is flat and well circumscribed and generally
less than 1cm in diameter. Saying that it is a papule means that it
is also solid and elevated above the rest of the skin. Classically
we associate this kind of skin eruption with a reaction to taking a
specific drug. Amoxicillin has been know to do this in a notable
portion of the population.