When discussing diction in poetry, we are looking for a range of ways in which the poet uses words to construct an experience and advance a view of the world or of the human experience. Because poetry typically seems more self-aware than prose (more overtly attentive to word order, line and stanza breaks), and because poems are typically more compressed and abstract than ideas written in prose, we often see diction as a most telling element in lyric poems.

Diction can sometimes refer to how the speaker uses language to create a level of formality. In this case, we might speak of elevated, formal, erudite, slang, colloquial and other markers of seriousness or intimacy. In Tennyson's poem—an elegy or sorts—the speaker is formal, in control of his thoughts and sentiments, claiming readiness for death as a "crossing of the [sand]bar" between life and afterlife.

The stateliness that accompanies contemplation of one's own death, when one seems ready to go, marks the metaphors as well. Diction also refers to word choice—this word not that similar word—to convey the connotation of a thought. Here, Tennyson uses familiar concepts—sailing, the sandbar, the Pilot, elements of nature such as the sunset, the star, the tide—but in a metaphorical pattern that elevates them and lends them greater dignity. Referring to God as the Pilot also elevates and somewhat mystifies the experience the poem describes.