Charles Douglas Smith Tennant CBE (1906 – 19 November 1985) was a British trade union leader.
Tennant came to prominence in 1935, when he helped to found the Navigators' and Engineer Officers' Union (NEOU).
In 1940, the IMMOA evacuated to London, and Tennant was appointed as its acting general secretary, soon winning the post on a permanent basis.
[1][2] After the war, Tennant felt that officers in the merchant navy were better represented by the International Transport Workers' Federation, and so in 1948, the IMMOA transferred all its industrial functions to that body.
[3][2] Tennant was made a Commander of the Order of the British Empire in the 1952 New Year Honours.