soupier

As a noun souper

is (ireland|historical) someone who, during the irish famine, supplied food such as soup to catholics who converted to protestantism.

As an adjective soupier is

(soupy).

As adjectives the difference between soupier and soppier

is that soupier is (soupy) while soppier is (soppy).

As adjectives the difference between soupier and soapier

is that soupier is (soupy) while soapier is (soapy).