This is the 4608th most frequent Catalan word.
plàcid
Calm; peaceful; serene.
The word 'plàcid' is used as an adjective here to describe the calm and peaceful nature of the place.
Aquest és un lloc plàcid per descansar.
This is a placid place to rest.
In this sentence, 'plàcid' is also an adjective modifying 'somriure', indicating a serene and calm expression of the child.
El somriure plàcid del nen reflectia felicitat.
The placid smile of the child reflected happiness.
Here, 'plàcid' describes the state of the environment at home, showing it has returned to a peaceful and undisturbed condition after the chaos.