Crumbles

Part of speech: Verb

Definition: to break into small pieces.

Source: Merriam-Webster Dictionary

The word is found in the Amy Lowell poem Alien, in the fifth and final line.

“My spirit crumbles at their teasing touch.”

She is using the word a s a verb to an action but is using figurative language to exaggerate her feelings because her spirit cant be broken into little pieces.