Bloop (noun)

1. A short, muffled, or indistinct sound.
2. A sound made by a submarine's sonar when detecting an object or anomaly in the water.
3. An unexpected or anomalous occurrence in a scientific experiment or data set.

Origin:

Onomatopoeic, imitative of the sound of a blip or other brief sound.

Examples:

1. The baby's first word was 'bloop', much to the amusement of her parents.
2. The submarine's sonar emitted a series of bloop sounds as it searched for enemy ships.
3. After analyzing the data, the scientists noticed a bloop that could not be explained by their models.