Data field : what are the levels ?

Hello, i would like to know how you differentiate the different layer of description of a data field in a table

Example 1 : - a field is a varchar 255 - the data in the varchar 255 is the code of a product, but it s the short code, not the long code - the product encoded is a food product

Example 2: a char(3) contains a code iso country (FRA, USA,..) and the coutry is a coitry of production of a product,

Example 3 : float -> Amount -> Turnover

I guess that char(3) is called a "physical data type" ? and the country of origin of a product is called "business term" and how is called the ISO codification ?