ADJ.
bright, red
PREP.
on
ADV.
fully
noun
A small accumulation of pus in the epidermis or dermis.
A pimple filled with pus.
Pigmy pagodas sprouted like pustules.
Anything like a pustule, on plants or animals; a small blister.
A bright red pustule began forming on Haziq's nose during dinner.
About the eighth day, the pustule is fully formed, when symptoms of small-pox are usually felt,—headache, shivering, loss of appetite, etc.