vs
QUICK ANSWER
"Estornudos" is a form of "estornudo", a noun which is often translated as "sneeze". "Tos" is a noun which is often translated as "cough". Learn more about the difference between "estornudos" and "tos" below.
el estornudo()
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
la tos()
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).