A former Girlguiding leader has urged the group to label itself as "mixed-sex" rather than "female only".
Dr Katie Alcock launched legal action after having her membership halted for objecting the decision to allow boys who identified themselves as girls to join.
Girlguiding later reached an out-of-court settlement with Dr Alcock, while also hinting that she could be welcomed back into the organisation.
But Dr Alcock has taken a fresh dig at Girlguiding, saying that the association should get rid of its status as single-sex.
Dr Katie Alcock
Twitter/@wontsomeonethi2
Girlguiding Chief Executive, Angela Salt
Girlguiding
She said: “Women are still discriminated against in this society, and until that changes they still need [the] Guides as a single-sex space."
Despite her concerns, Dr Alcock has described how her expulsion left her feeling like she had “lost part of the meaning of life”.
Dr Alcock told the Sunday Times: “I had some sleepless nights. I had been involved for so long with the Guides and it meant so much to me.
“I just want it to carry on, allowing other girls to grow up having wild adventures and fun, outdoors, with other girls and female mentors.
“When I was expelled, it meant I lost all those friends. Leaders who I’d done playdates with, with my kids, now didn’t talk to me at children’s events."
A statement released by Girlguiding after settling the case with the former leader said it has taken her concerns “seriously” and will “reflect this in the language we use”.
The statement read: “We have listened carefully to Katie’s concerns. We understand them and take them seriously. Whilst these are complex and evolving issues, we agree that sex and gender are different, and will reflect this in the language we use.
“The safeguarding and wellbeing of girls has and will always be at the heart of everything we do … Our priority is to ensure that we offer a safe space where all girls are welcome to have fun, learn, and grow, and feel that they can be who they truly are.”
A spokesperson for Girlguiding told the Telegraph: "Through fun, friendship, challenge and adventure we empower girls to find their voice, inspiring them to discover the best in themselves and make a positive difference in their community.
"By giving girls a space just for them, girls feel free to be themselves.
"We are a girl-only charity, our membership is open to those who are biologically female and those whose gender is a girl or woman.
"Girlguiding has no plans to change how it describes itself as a girl-only charity."