Final answer:
The medical term combining 'middle' and 'side', along with the suffix '-al', is 'mediolateral', meaning pertaining to both the middle and the side.
Step-by-step explanation:
To construct a medical term that means 'pertaining to the middle and to the side', we leverage our understanding of anatomical orientation. 'Medial' describes a position toward the middle of the body, while 'lateral' refers to a position toward the side of the body. By combining these with the suffix -al, which denotes 'pertaining to', we can create the term 'mediolateral', which describes something pertaining to both the middle and the side of the body.