In "Bright Star! Would I Were as Steadfast as Thou Art," the speaker repeats "still" (13).What relevant denotations does the word evoke? How does the repetition add intensity and meaning to this apostrophe? Why is an apostrophe more effective here than a description of the star that does not address it?
The word "still" marks a change of tone in the poem. Keats has been expressing the thought that he wishes he could be eternal as a star that watches alone over "moving waters" and "the soft-fallen mask/ Of snow." But he "still" wants to be able to love another person and he knows that he cannot do so alone. The word "still" marks one change in his final attitude. It also emphasizes the ideas above it in lines 1-12. A star is "still" yet in it stillness, it cannot "hear her tender taken breath". So, there is a double meaning to the word. It marks the eternal nature (or stillness) of of a star yet it is also a transitional word which moves his thoughts forward to the place where he realizes that would mean not being able to love one who breathes "the tender breath". "To love, he must be human" and therefore not "still" as a star.
The possible denotations of that repeated "still" are the possible literal definitions of what still means. First of all, it means holding one's position for a long time, not moving, remaining immobilized. This is significant because he wants to remain with his love, feeling her "ripening breast" and "tender-taken breath", while remaining completely still and motionless, just like the stars are, which he talks about in the first part of the poem. The second possible definition of still is to remain somewhere, to continue to be there. This signifies his desire to be forever with his love, and to never leave her. So, "still" refers to how he wants to lie motionless, with his love, forever and ever.
It adds intensity to repeat "still" because it brings to mind a child asking impatiently, "Are you still busy?" or something to that effect. The parental response is, "Yes, still", so to repeat it twice is to emphasize it, to repeat it to any inquiring minds. Yes, he is still there, still with her, and please be still about it. This is more effective than describing the star, because it encapsulates the quality of a star that he is desiring the most-its immovable eternal nature-without having to decribe it in detail. It conveys the emotion behind that much more efficiently than long and wordy details.