Question

What term is used for a line that includes several words that begin with the same letter?

Answer 1

Alliteration

Explanation:

Keep in mind that the words need to be either next to or quite close to each other. So this works:

Aunt Agatha ate all the apples. (The word "the" doesn't prevent "apples" from being part of the alliteration).

but this doesn't:

Aunt Gertrude ate most of a bag of apples in April.

http://literarydevices.net/alliteration/