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seul
/sœl/
alone, only
Il vit seul depuis dix ans.
He has lived alone for ten years.
general
Adjective of solitude: alone, on one's own.
Il vit seul depuis dix ans.
He has lived alone for ten years.
Agrees: seul, seule, seuls, seules.
general
Placed before a noun, means only or single.
Un seul mot et tu es puni.
One single word and you're grounded.
Un seul = only one; le seul = the only one.
Word Origin
From Latin solus (alone, only).
Dictionnaire Français-Anglais