In literature, metaphysical refers to what is other than the physical, earthly realm—the area usually associated with the spiritual or unexplainable, or with exploring the nature of existence in both its spiritual and material forms.
Like many metaphysical poets, Dickinson tried to capture a sense of the ineffable or supernatural in terms of imagery, description that uses any of the five senses of sight, sound, taste, touch, or smell. One example would be her poem "The Only Ghost I Ever Saw." In it, she tries to capture the intangible, fleeting sensation of what it is to have a ghostly vision. Her ghost is dressed in "mechelin" or lace, a material with an airy, insubstantial quality, and he wears "no sandal." The ghost is compared to objects or animals in the physical world that are fleeting or very delicate, almost as if not there: his step is "like flakes of snow," silent and quick to dissolve, he is "soundless" like a bird but also flashes by rapidly, "like the roe," or a small deer. This poem puts into concrete imagery what a flashing glimpse of an otherworldly creature might be like.
Dickinson's most famous metaphysical poem is probably, "Because I Could Not Stop for Death." In this poem, Dickinson tries to describe what death—or the journey from life to death—might feel like in imagistic terms. Death itself is personified as a gentleman, and the journey to the grave imagined as a carriage ride, with the carriage moving slowly, a sunset in the background, the weather turning chilly, and the loss of the corporeal body described as like being dressed in "gossamer," a very thin, light, translucent cloth.
In both these poems, the supernatural or transcendent enters the poet's imagination, and she tries to describe these realms.