Alone in a given category
Not divided among or shared with others
Without a spouse
His own voice was the sole reply.
I was miffed that I was the sole person burdened with straightening out this mess.
Protective of his sole treasure, he had never entrusted anyone else with guarding it.
Gladys Turnbull remained Bird Song's sole paying guest, at least for a couple of days longer.
Lifting his foot, he struck the match on the sole of his shoe.