Not interesting or memorable enough to remember; easy to forget.
From Old English 'forgietan' (to forget) + '-able' suffix meaning 'capable of being.' The modern form emerged in the 1600s to describe things not worth remembering.
Ironically, 'forgettable' is a word we use to describe things we can't remember—it's the linguistic equivalent of a paradox, like naming something 'nameless.' The word exists because we needed to talk about the forgetting process itself!
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