other
alone, by oneself
A1
'allein' means 'alone' or 'by oneself'. It functions as adjective or adverb, used predicatively ('Ich bin allein') or adverbially ('Er lebt allein'). No special preposition or reflexivity. Note: variant 'alleine' exists colloquially. It can also mean 'only' in formal contexts ('Allein das Wetter'). Antonym: 'gemeinsam'.
Examples
Er lebt allein in der Stadt.
He lives alone in the city.
Die Frau blieb allein zu Hause, obwohl ihre Freunde mehrmals anriefen.
The woman stayed alone at home even though her friends called several times.
Ich mache die Hausaufgaben allein.
I do the homework by myself.
Details
Mnemonics
Picture a single person standing on a lane to recall 'alone'
allein ~ 'a-lane' (alone) to remember solitary sense
n/a
Notes
Input lacked a POS tag. 'allein' is commonly used as an adjective or adverb meaning 'alone' or 'by oneself'.