Usually when doing GIS projects, especially when working as a freelancer, you're just provided with a bunch of shapefiles and you have to figure out yourself what all the table attributes mean. Because shapefiles have a *.dbf limited character number for naming attribute fields, the names are usually abbreviations. Is there a way to add a description of the attribute field names when creating them, or how do you add attribute field metadata. What do you do when you don't understand the abbreviations of a shapefile attribute table metadata that has been created by someone else?
I just did a quick test of creating a shapefile and then used ArcMap 10.2 to access the Metadata tab of Customize | ArcMap Options where I set the Metadata Style to ISO 19139 Metadata Implementation Specification (but the other choices are likely to behave similarly).
In the Catalog window I accessed the Item Description of the shapefile and clicked Edit to start editing its metadata. In the Resource section in the lefthand panel I found Fields and when I opened one of the fields in the righthand panel I found a Definition type-in area that looks like what you are after.
When the shapefile provider Saves the metadata it gets written to an XML file called .shp.xml that gets copied with the remainder of the shapefile so you should be able to open it up in Item Description.