A rounded lump or drop of thick liquid substance, or to form into such a shape.
Imitative/onomatopoetic origin from 1500s, possibly influenced by 'bleb' (a blister). The word mimics the sound or sight of something soft and amorphous dropping or forming.
Computer programmers call large binary files 'blobs' (Binary Large Objects) because they're shapeless chunks of data—showing how old descriptive words get recycled for modern technology.
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