grumble
This word evokes a sense of low-frequency sound, whether it is the physical vibration of thunder and digestion or the muted tone of a dissatisfied person. It suggests a lack of openness or courage; a grumble is not a loud protest or a formal complaint, but rather a muttered, half-hearted expression of annoyance. When used as a noun, the word can refer to a singular sound or a collection of complaints. While the sound of thunder is typically treated as a singular phenomenon, the complaints of people are often pluralized to indicate a series of repeated grievances.
Meanings
To complain about something in a low voice, often in a way that expresses dissatisfaction or annoyance.
"He continued to grumble about the cold weather throughout the trip."
To utter low, guttural sounds of complaint or dissatisfaction.
"She grumbled a few words of protest before agreeing to the plan."
To make a low, rumbling sound, typically referring to the stomach or thunder.
"My stomach began to grumble during the long meeting."