This is the 5171st most frequent Russian word.
недовольство
Dissatisfaction.
In this sentence, 'недовольство' is used as a noun to describe a general feeling of dissatisfaction or discontent, which is directly related to the person's expression.
Его недовольство было заметно по выражению его лица.
His discontent was evident in his facial expression.
Here, 'недовольство' functions as the subject of a declarative action, indicating a communicated sentiment of dissatisfaction.
Она выразила своё недовольство из-за задержки.
She expressed her dissatisfaction about the delay.
In this example, 'недовольство' refers to a collective sense of discontent among a group, relating to external circumstances.