What does the cryptic crossword clue "Anti-labour slogan in this sub-Saharan speech? (5)" mean?

The definition is "s". The wordplay uses a homophone (sounds like). BAN (synonym="BAN") + TU (synonym="ban trade union") = BANTU The answer is BANTU.

Anti-labour slogan in this sub-Saharan speech? (5)

Guardian Cryptic #28927 | 23 Down | 2022-11-29 flower