noun
plaster (bandage), pavement, cobblestone pavement
B1
Pflaster (das) has two common meanings: a plaster/bandage (small adhesive bandage) and cobblestone pavement. Gender: neuter. Plural: Pflaster (unchanged). Declension regular. Context determines meaning: medical (ein Pflaster kleben) versus urban/road (auf dem Pflaster laufen). No irregular plural. Used in everyday language.
Examples
Das alte Pflaster in der Altstadt ist uneben und schwierig zum Laufen.
The old cobblestone pavement in the old town is uneven and hard to walk on.
Das Pflaster vor dem Haus ist nach dem Regen sehr rutschig.
The pavement in front of the house is very slippery after the rain.
Ich brauche ein Pflaster für meine Blase.
I need a plaster for my blister.
Details
Mnemonics
Imagine a small adhesive bandage (plaster) stuck to a knee; that visual links the word to wounds and first aid.
Sounds like English 'plaster' (a bandage) — same basic word in meaning.
das (neuter) — think of a small neutral-colored 'patch' labelled 'das' stuck on the skin.
Notes
Pflaster can mean an adhesive bandage (British English 'plaster', American English 'band-aid' or 'adhesive bandage') or the paved surface made of stones (pavement/cobblestones). Context tells you which meaning is intended: at a pharmacy it's the bandage sense, in urban descriptions it's the paving sense.