Final answer:
In musical terminology, the ternary form is represented by ABA, where the first section is repeated after a contrasting middle section.
Step-by-step explanation:
Based on the knowledge of musical terminology, the form referred to as ternary is represented by the letters ABA. In ternary form, the music is divided into three sections, with the first section (A) being repeated after the contrasting middle section (B). An example of ternary form could be a simple minuet and trio where the minuet is the A section, the trio is the B section, and then the minuet (A) returns.