Emily Dickinson Lexicon

letting, verbal n. [OE lætan.; gerund form; see let, v.]

1. Phrase. “The letting go”: [intransitive] acceptance; realization of irreversible events; recognition of a fact that cannot be changed; [fig.] death; demise; end of life; allowing oneself to die without resisting the transition; [metaphor] resignation; emotional paralysis.
2. Phrase. “The letting go”: [transitive] concession of; release of; yielding of; relinquishment of; giving up of (someone); loosening of one's hold on (something).