1. 无人照料的；无人看管的
When people or things are left unattended, they are not being watched or looked after.

1. lacking a caretaker

e.g. a neglected child
many casualties were lying unattended

Synonym: neglected

2. lacking accompaniment or a guard or escort

e.g. unattended women
problems unattended with danger

3. not watched

e.g. she dashed out leaving the bar unattended
a fire left unattended