I would suggest paper dictionaries, pre -1990 editions for 'original' (i.e. establisehd) meanings of words.
This made me ruefully reflect upon the paper dictionaries I have thrown out, and I remember a Collins dictionary I once had, so I looked for the online version and it defines ‘gender’ far more in keeping with its British usage (since the appearance of ‘gender identity’) IME.
Definition of 'gender'
gender
(dʒendəʳ )
Word forms: plural genders
1. UNCOUNTABLE NOUN Gender is the state of being male or female in relation to the social and cultural* roles that are considered appropriate for men and women.*
It is illegal to discriminate on the grounds of race, gender or sexual orientation.
Gender stereotyping can be as damaging for men as it can for women.
Some people experience a mismatch between their gender identity and their biological sex.
2. COUNTABLE NOUN You can use gender to refer to one of a range of identities that includes female, male, a combinationof both, and neither.
Membership is open to people of all genders.
The new law would allow people to change gender by filling in a form.
Each of them identifies with a different gender from the one they were born with.
3. VARIABLE NOUN Some people refer to the fact that a person is male or female as his or her gender.
Women are sometimes denied opportunities solely because of their gender.
4. COUNTABLE NOUN Some people refer to all male people or all female people as a particular gender.
...the different abilities and skills of the two genders.
5. VARIABLE NOUN In grammar, the gender of a noun, pronoun, or adjective is whether it is masculine, feminine, or neuter. A word's gender can affect its form and behaviour. In English, only personal pronouns such as 'she', reflexive pronouns such as 'itself', and possessive* determiners such as 'his' have gender.*
In both Welsh and Irish the word for 'moon' is of feminine gender.
Word Frequency
gender-
(dʒendəʳ )
COMBINING FORMGender- combines with adjectives to refer to things that relate to people's gender or to people who have a particular gender identity.
Each electoral list must be as gender-balanced as possible.
In usage #3 - it is ‘some people refer to’ - [just like ‘some people’ use the word ‘literally’ to mean ‘figuratively’ - ie - wrong].
In usage #4 - the same - ‘some people refer to’.
Just because ‘some people’ use a word in a certain way, it doesn’t mean that this is was the word actually means.
https://www.collinsdictionary.com/dictionary/english/gender