A retired police officer says she was investigated by her former colleagues after she 'dead-named' a transgender woman on the internet.

Cathy Larkman, who served with South Wales Police for more than 30 years, was told her home visit was related to a series of social media posts about transgender activist Freda Wallace, The Telegraph reports.

Dead-naming is when a transgender person is called by their birth name instead of the name they chose after they transitioned.

The former superintendent had called the activist Fred, in other words using the 'dead' male name of the now transgender woman.

Larkman was not at home when police showed up at her door, but she was told a report had been made over her possible 'malicious communications'.