Emily Dickinson Lexicon

COM-PACT', a. [L. compactus, compingo; con and pango, pactus, to thrust, drive, fix, make fast or close; antiq. pago, paco; Gr. πηγνυω. See Pack. Literally, driven, thrust or pressed together. Hence,]

1. Closely and firmly united, as the particles of solid bodies; firm; close; solid; dense. Stone, iron and wood are compact bodies. A compact leaf, in botany, is one having the pulp of a close firm texture.
2. Composing; consisting. A wandering fire, / Compact of unctuous vapor. – Milton. Shak. This sense is not common. [See the verb.] Compact seems to be used for compacted. So in the following example.
3. Joined; held together. [Little used.] A pipe of seven reeds, compact with wax together. – Peacham.
4. Brief; close; pithy; not diffuse; not verbose; as, a compact discourse.