The door key (Symbol)
The door key is at once a real, concrete object in the world of the poem and a symbolic stand-in for an entire class of objects. It represents the mundane, everyday objects that populate the speaker's world. Since ownership, in this poem, is inextricable from loss, the key is symbolic of minor losses. These losses may be annoying, but they aren't terribly upsetting. The choice of a key to symbolize a small loss is fitting: it is a small, inexpensive object that is relatively easy to replace, but that nonetheless has noticeable effects when it is lost. Since a key is something that grants access to something else, the loss of this small object has broad implications.
Lost travel memory (Symbol)
Among the losses the speaker lists are a memory of "where it was you meant/to travel." While this certainly refers to the simple act of forgetting, this particular object of forgetfulness also symbolizes the resignations that come with aging. The phrase is complex, and symbolizes a complex variety of disappointment. It does not, for instance, simply symbolize the forgetting of cherished travel memories, or even the missed opportunity that comes with not traveling somewhere. Rather, it symbolizes the entire experience of resigning oneself to, and entirely moving on from, previous disappointments. The speaker has evidently lost not only certain hopes about travel, but also their previous, youthful sense of possibility.
The mother's watch (Symbol)
The mother's watch, quite straightforwardly, symbolizes the relationship between the speaker and their mother. While the exact nature of their relationship is not known (indeed, it is not even clear whether the mother is alive or not), the lost watch symbolizes an event that created distance between the two. This event might be the mother's death, might be a fight or conflict, or might simply be the slow erosion of the speaker's memories of the mother. A watch, of course, is used to tell time, hinting that time has played a role in altering the relationship between the speaker and the mother. Again, this could mean many things. Perhaps time has aged the mother and she is no longer alive. Perhaps time has simply made the speaker and the mother grow apart.
Geography (Motif)
As the losses listed in "One Art" grow more exaggerated and bigger, the poem's scale shifts from the human to the geographical and topographical. The listed images, in this part of the poem, include rivers, cities, realms, and continents. Intriguingly, these images are markedly vague and nonspecific. Most people have trouble picturing a continent, except as a form on a map. The word "realm" is so vague, in fact, as to be nearly meaningless. Poets generally aim for great vividness and specificity, so it's worth questioning why Bishop does the opposite here. One explanation is that she's trying to provide an example of the biggest, most dramatic loss possible. Viewed through this lens, it makes sense that she'd opt to use geographical motifs: they're so big and dramatic that they're impossible to picture.
Skill (Motif)
"One Art" frames loss, usually considered an unintentional and undesirable situation, as a skill to be honed and actively sought out. As such it employs motifs of work, practice, and competence. These include the word "master" (used as a verb) and a series of instructions describing how to "practice" loss. The poem also builds up from small losses to big ones, coaching the listener on how to move from novice status to mastery (in this sense, the poem progresses a bit like a training montage from a sports movie). The speaker, in the end, seems to falter, unsure whether it's really true that loss can be mastered like any other skill. But regardless, motifs of skill and practice dominate the poem, prompting the reader to interrogate whether it's possible or helpful to attempt mastery of loss.
