single-handedly

adverb
UK /ˌsɪŋ.ɡəlˈhæn.dɪd.li/
US /ˌsɪŋ.ɡəlˈhæn.dɪd.li/

all by yourself, without help from anyone.

She single-handedly built the whole treehouse.


OTHER MEANINGS

2. using only one hand.

He caught the ball single-handedly.

3. done by one person rather than a team.

The rescue was a single-handedly brave act.

4. without support from others in a difficult task.

She single-handedly kept the family business running.