A native of Charlottetown, Prince Edward Island, MacEwen of Scottish descent from his great grandmother on his father's side. He was raised in Stratford, PEI while his family ran a berry farm.

MacEwen played minor midget hockey with Pownal Red Devils and signed with Moncton of the Quebec Major Junior Hockey League in 2014 after two seasons playing for Amherst, a Junior A Hockey League team in the Maritime Hockey League. He scored 40 points (10 goals, 30 assists) in 66 games of his first full season in 2015-16 and attended Anaheim Ducks training camp before being returned to the QMJHL. MacEwen was traded to Gatineau on Aug. 11, 2016.

The undrafted center signed a three-year, entry-level contract with the Vancouver Canucks on March 3, 2017 and an amateur tryout contract with Utica of the American Hockey League on Oct. 29. He ended his first pro season with 33 points (10 goals, 23 assists) in 66 AHL games and won the Ian Anderson Award given to Utica's top rookie.

MacEwen started 2018-19 in Utica and recalled Feb. 10, one night after a four-point game against Rochester. He made his NHL debut and scored his first NHL point, an assist, in Vancouver's 7-2 loss to the San Jose Sharks on Feb. 11. He scored his first NHL goal in a 5-2 win against the Ottawa Senators on Dec. 3 and scored six points (five goals, one assist) in 17 games before the 2019-20 season was paused March 12 due to concerns surrounding the coronavirus.

NOTES & TRANSACTIONS

• Signed as a free agent by Vancouver, March 3, 2017.
• Claimed off waivers by Philadelphia from Vancouver, October 13, 2021.