A small or insignificant dream, or a brief dream fragment.
From dream + -let (a diminutive suffix meaning 'small one'). The suffix -let comes from Old French -elet, originally from Latin -illus, used to create terms for smaller versions of things.
The diminutive suffix -let appears in everyday words like 'booklet' and 'droplet,' but literary authors used 'dreamlet' in the 19th century to describe those fleeting, half-remembered dreams that vanish the moment you wake up.
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