Borderline attention deficet / with hyperactivity, borderline meaning on a mild sign and not full blown ADD. Borderline too in a sense is that it may overlap with other mental disorders, for example a person can be Bipolar and Add, a person can have multiple disorders, or just borderline between the "norm" and the ADD/ADDHD.
One can be ADD and not hyperactive, daydreams a lot, not showing as being a hyperactive person but still suffers with it.
This type usually goes unrecognized as opposed to those who are hyperactive. Back in my younger days, nothing was known about this either you were a kid with "ants in your pants" (metaphor) with possible undesirable behaviour,and didnt pay attention or you were more like quiet, daydreaming, and would miss out on a lot due to daydreaming, sometimes when I would look at a teacher I saw her lips moving and sound but not really was focus on what she was really saying.
This disorder has many variants, sometimes confused with learning disabilities, a whole other can of worms
I believe at the home page here you can look this up, if not on the internet, there are loads of informative sites and books you can either purchase or get from the local libraries too.

In giving advice seek to help, not please your friend
SOLON