Hamonic, 31, is a defensive-first player who had seven points in 24 games for the Canucks, averaging 18 minutes, 22 seconds in ice time per game. Hamonic is in his 12th NHL season, having previously played for the New York Islanders and Calgary Flames.
Hamonic is signed through 2022-23 with a $3 million cap hit, after which he'll be an unrestricted free agent. His salary is $3.25 million next season. He had a modified no-trade clause of eight teams.
The third-round pick shipped to Vancouver was the Canucks' own 2022 pick. Vancouver originally traded that pick to the Vegas Golden Knights in 2020 for defenseman Nate Schmidt. Vegas traded that pick to Ottawa in 2021 for forward Evgenii Dadonov.
The Canucks did not retain any salary in the trade. Vancouver, which lost to Calgary on Saturday night, is five points away from the final playoff berth in the Western Conference.
Dermott, 25, is a solid third-pairing player who averages decent minutes (14:43 a night) and has five points in 43 games this season. He signed a two-year, $3 million extension with Toronto as a restricted free agent last summer but has since struggled to find a place in the Leafs' crowded crop of bottom-pair blueliners.
Dermott has repeatedly been a healthy scratch in recent weeks, and it seemed inevitable Toronto would try to find him an opportunity elsewhere.
The Canucks are a team in transition, as evidenced by the Hamonic trade, and should have room for Dermott to find his game again.
ESPN's Kristen Shilton contributed to this report.