Keening

The keening whistle of the tea kettle signaled that the water had boiled.

The keening whistle of the teapot signaled that the water was boiling.

The widow sat alone in her empty house, keening softly for the husband she had lost.

The keening smell of rotten eggs filled the kitchen, indicating a gas leak.

The keening smell of rotten eggs indicated a gas leak in the basement.

The lonely lighthouse emitted a keening beam of light that swept across the dark sea.

The eerie keening of the siren warned the residents of the impending storm.

The injured bird emitted a keening cry, signaling its distress.