reading a name from collumn in a formula

Hello,
plz how can i achieve this:

I have several columns named in excel - for example adam is name for column Z1:Z100,
eve is column x1:x100

than i have cells where is written the word , for example in cell A1 is written adam

then i want to add a formula to another cell that refers to A1,reads the adam there and in the end uses Z1:Z100


so if i write =avg(adam) that works properly, but i want excel to read the adam from A1
something like do avg from column which name is written in A1

hope you understand my explanation, there is an explanatory doc attached also

THX for answers

THX very much