Butterfly (Metaphor and Simile)
Throughout the opera, Madame Butterfly is referred to as a butterfly and "like a butterfly" at many points. Her name itself is a metaphor, conflating her identity with that of a butterfly. Then, in "Amore o grillo" she is referred to as "like a butterfly."
"A smile is perfume of gods" (Metaphor)
When Suzuki, Butterfly's maid, first meets Pinkerton, she admires his smile and uses this metaphor to describe it. She suggests that smiling is a perfume sent by the gods, a kind of spiritual fragrance that blesses others.
"Life's not worth living unless he can pick the flowers on every shore" (Metaphor)
Pinkerton uses this metaphor in his first aria to describe the fact that he wants to be able to have sex and conquer women romantically all over the world. He uses the euphemism of picking flowers to describe this colonialist sexual attitude.
"Little orange blossom" (Metapor)
One of Pinkerton's nicknames for Butterfly is "little orange blossom." The blossom of the orange tree is sweet, delicate, and does not last long. It is similar to the metaphorical nickname of "butterfly" in that it foreshadows her doom.
"Her heart is beating wildly like the wings of a caged bird" (Simile)
Suzuki uses this simile to describe how anxious and activated Butterfly is just before committing suicide. She compares her heart to the wings of a bird that is trapped, which reflects the horrible inevitability of Butterfly's sorry fate.