'Weak minded'

[Roobarb]

I have copies of some (lunatic) asylum records from the early part of the twentieth century. In one of the columns it lists contributory factors and the comment is Heredity (Mother weak minded). The person in question was suffering from Acute Melancholia, which I'm sure these days we would term Acute depression.
I've trawled unsuccessfully through all sorts on the internet to find an exact definition of what at the time was the meaning of weak minded. I found something that said depression was viewed as a weakness - does it then mean that his mother also suffered from depression, or was it something else?

Much as I appreciate ideas and comments from people I'm looking this time for a definitive explanation of what was clinically meant by this term at the time, perhaps a reference to a document. Would appreciate if anyone has access to information of that nature. 

[DonM]

Merriam says:

https://www.merriam-webster.com/dictionary/weak-minded

And to be really confused:

https://www.thesaurus.com/browse/weak-minded

Don

[Romilly]

I can be very weak minded over chocolate, - especially at Christmas...

Romilly 

[Roobarb]

Thanks Don, I was looking for a more a specific definition of what it meant clinically at the time rather than a dictionary definition.

Romilly,  I think there are many who fall into that category! 

[Mike in Cumbria]

This is the nearest I can find, and refers to feeble-minded rather than weak-minded.

In the past, some terms had a formal definition in the UK; however, they have been discontinued:
IQ = 130+ Gifted
IQ = 70+ Normal
IQ = 0 to 25 - Idiot - Severe learning disability
IQ= 25 to 50 - Imbecile - Moderate learning disability
IQ = 50 to 70 - Moron or Feeble Minded - Mild learning disability
An individual with an IQ of less than 50 usually requires care throughout their life and they are unlikely
to be educable in the formal sense.

https://campbellmgold.co.uk/archive_esoteric/morons_imbeciles_idiots.pdf

[Roobarb]

Thank you Mike, that gives me a better idea of it. 

[markheal]

Roobarb,
My holiday challenge.
Have you noticed that on most asylum census records the 'inmates' are listed only  by initials.  This can present a real challenge when hoping to find these peoples' family before and after their spell in the asylum.  Three initials are of course easier than just two!