No
That term refers to a lower than a 70 IQ. There are no other disabilities that cause the low IQ.
A normal IQ is usually 70 and up. Stephan Hawkins in supposed to be close to 195 but he is an exception.
A person diagnosed with Mental Retardation has an IQ of 69 or less and has no other diagnosis that causes this lower IQ.
For example, Downs' syndrome is a diagnosed disability and one of the parts of it is lower IQ but it is also a processing information issue among a whole list of other things. The lower IQ is part of their disability but not the whole disability.
A person who has a low IQ can be normal in looks, normal in the way they process the world, normal in the way they relate to family and friends. They can marry, have normal kids, have high school diplomas, etc....they just have a harder time learning and it takes them more time. Some things will obviously be out of reach mentally for them, such as higher mathematics and chemistry but pretty much everything else can be accomplished that is basic common knowledge. They can have harder times in certain areas of thinking, such as their spatial abilities. They might go to Walmart every day of the week and still not be able to find their way to the front doors.
Someone that has Autism falls into a totally different category of disability.
Learning disabilities are diagnosed when a person is having a hard time in one or a few areas of learning. They may not be able to understand math well but excel in every other subject. I have a friend who owns her own successful business and runs it very well. She provides for her family and makes lots of money. She has several diagnosed learning disabilities that effect her math skills and spelling. She has an accountant to do the math and she has an assistant to do any writing of letters. She is very smart and is not disabled in any way because she adapted her environment to her needs.