terminology for square roots

[Joseph Biberstine]

Each positive integer has a square root uniquely expressed a product 
a*sqrt(d), where a and d are positive integers and d is squarefree.

What's the standard terminology for the parts a and d of some sqrt(n)?

Some options for a: integer part, ..?

Some options for d: quadratic part, radicand, squarefree part, radical 
part, ..?

Anyhow, the "a-part" and "d-part" of the square root of many fundamental 
integer sequences are absent from EIS.