What is the definition of andesitic composition?

Andesite:

Is an extrusive igneous, volcanic rock, of intermediate composition, with anphanitic to porphyritic texture. In a general sence, it is the intermediate type between basalt and decite and ranges from 57 to 63% silicon dioxide as illustrated inTAS diagrams.

Andesite can composition is a rock composed essentially of plagioclase feldspar and one or more mafic minerals, as hornblende or biotite.