bottomless feeling

In terms of language, leaping is the ability to associate fast. In a great poem, the considerable distance between associations, that is, the distance the spark has to leap, gives the lines their bottomless feeling, their space, and the speed (of association) increases the excitement of the poetry.
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We often feel elation when reading Homer, Neruda, Dickinson, Vallejo, and Blake because the poet is following some arc of association that corresponds to the inner life of objects he or she speaks of, for example, the association between lids of eyes and the bark of stones [de Nerval’s poem "Golden Lines"]. The associative paths are not private to the poet, but are somehow inherent in the universe.
[…]
The poet who is “leaping” makes a jump from an object soaked in conscious psychic substance to an object soaked in latent or instinctive psychic substance. One real joy of poetry—not the only one—is to experience this leaping inside a poem.

—Robert Bly, “Looking for Dragon Smoke,” American Poetry: Wildness and Domesticity (Harper & Row, 1990)

known by association

The poet denied he was part of that group/school/movement, when the only reason anyone knew his work was because of that association.

well-spring

Each word was a well of associations.

stuck here & there

After the critic got finished with the poem it was a pincushion of far-fetched associations.