A direct comparison is a metaphor.
Sonnets are 14 lines love poems common for the renaissance period while blazons are often paired up with sonnets because they are poems where women are compared to something else. Shakespeare did this in his sonnet 130 which was also kind of a parody of the conventions because he says that his loved one is not that pretty. A quatrain is a stanza of 4 lines and that sonnet has 3 quatrains and couplet.
