Speaker or Narrator, and Point of View
First-person lyric "I"
Form and Meter
Sonnet with rhyme scheme ABABBAAB CDC DCD, though not strictly following any traditional form (Shakespearean, Petrarchan, Spenserian, etc.). Sprung rhythm.
Metaphors and Similes
Heavily metaphorical, even when apparently descriptive, see, for example, the opening lines, as well as lines such as "rung upon the rein of a wimpling wind." Just one simile, however: "As a skate's heel sweeps smooth on a bow-bend."
Alliteration and Assonance
Heavily alliterative throughout, which on first reading can overwhelm some of the slightly more subtle poetic devices. Hopkins makes frequent and skillful use of assonance as well, however. The force of a line such as "daylight's dauphin, dapple-dawn-drawn Falcon, in his riding" is just as dependent on the recurrent, and varied, 'a's, modulating into the short "i" sounds at the end, as it is on the more attention-grabbing percussive series of 'd' sounds.
Irony
"Stirred for a bird" is the sole example of Hopkins using sonic devices for comedic/ironic effect in "The Windhover." The nursery-rhyme quality of this phrase suggests the speaker's surprise at the fact that something as ordinary as a bird in flight could produce such a deep, emotional reaction in him.
Genre
Lyric poetry, Victorian poetry, devotional nature poetry
Setting
Unspecified, but given that hunting kestrels are uncommon in populated areas, it's safe to assume the speaker is in the countryside (or was, at least).
Tone
By turns: ecstatic, intense, philosophical
Protagonist and Antagonist
n/a
Major Conflict
n/a
Climax
The first of the two tercets is, arguably, the climactic moment of the poem; narratively, it occupies the very place we'd expect a description of the hawk catching its prey. The language is abrupt, and words like "buckle" carry connotations of violence.
Foreshadowing
n/a
Understatement
n/a
Allusions
Some of the more striking diction in the poem, such as "minion," "dauphin," and "chevalier" are indirect allusions to the medieval concept, code, and social structure known as "chivalry." Hopkins draws on this resonance, and employs it as a way of exploring the speaker's relationship to faith.
Metonymy and Synecdoche
n/a
Personification
"My heart in hiding" is one key example of personification. The titular windhover is also personified, though mostly indirectly, such as when the speaker ascribes to the falcon an "ecstasy" which of course is in fact his own.
Hyperbole
The language often appears hyperbolic, but Hopkins' intention is to match, not overstate or exaggerate, the significance and intensity of the experiences and perceptions depicted.
Onomatopoeia
n/a
