Vocabulary in The Flea

The noun “jet” here refers to a semiprecious black stone. The speaker means that the inside of the flea is dark, which presumably enables the couple to better conceal themselves from discovery. Donne further emphasizes the sacred qualities of the flea’s body by comparing its appearance to that of a valuable stone.

The verb “to cloister” means to be sheltered from the outside world. A cloister is also a secluded walkway within a convent, church, or monastery. The religious connotations of Donne’s word choice indicates that the flea’s body is sacred; thus, the couple’s union within the flea’s “walls of jet” is not shameful.

The verb “to grudge” means to agree to something with reluctance. The speaker portrays the young woman’s protective parents as enemies from which they have hidden within the protective “living walls of jet” of the flea’s body. The reluctance of the young woman herself is shown through her inclusion in the “grudge,” but the speaker argues that their union has already happened within the flea.

The noun “maidenhead” is another term for a woman’s virginity, which was highly valued in 17th-century England. The poem’s speaker attempts to convince his romantic interest that losing her virginity to him will carry no more sin or shame than a harmless flea bite.