Emily Dickinson Lexicon

DO-MAIN', n. [Fr. domaine; Arm. domany. This would seem to be from L. dominium. Qu. is it the same word as demain, which is from the old French demesne. The latter can not be regularly deduced from dominium, domino. The Norman French has demesner, to rule, to demean; and the phrase, “de son demainer,” in his demain, would seem to be from a different source. Mainor, in Norman, is tenancy or occupation, from main, the hand. Domain seems to be the L. dominium, and to have been confounded with demain, demesne.]

1. Dominion; empire; territory governed, or under the government of a sovereign; as, the vast domains of the Russian emperor; the domains of the British king.
2. Possession; estate; as, the portion of the king's domains. – Dryden.
3. The land about the mansion-house of a lord, and in his immediate occupancy. In this sense, the word coincides with demain, demesne. Shenstone.