- Arthur Stanley Lamb
- Arthur Sturgis Hardy
- Arthur Sutherland Piggott Woodhouse
- Arthur T. Doyle
- Arthur Thomas Bushby
- Arthur Thomas Howe
- Arthur Watkins Crisp
- Arthur Wellesley Hughes
- Arthur William Delamont
- Artificial Heart Developed
- Artificial Intelligence (AI) in Canada
- Artificial Mini-Hearts Developed
- Artiodactyla
- Artists' Jazz Band
- Artists' Organizations
- Arts
- Arts & Crafts
- Arts and Crafts Movement in Canada
- Arts and Culture Centre
- Arts and Letters Club of Toronto
