Question

what is meant by Avogadro atomic mass

Answer 1

Amedeo Avogadro

In chemistry and physics, the Avogadro constant(named after scientist Amedeo Avogadro) is the number of constituent particles, usually atoms or molecules, that are contained in the amount of substance given by one mole. Thus, it is the proportionality factor that relates the molar mass of a substance to the mass of a sample. The Avogadro constant, often designated with the symbol NA or L, has the value 6.022140857(74)×1023 mol−1[1] in the International System of Units (SI).[2][3] (The parentheses there represent the degree of uncertainty.)

A much simpler definition is that Avogadro's constant is the conversion factor for converting grams to atomic mass units.