Succinct, a. — Webster enters it under “succinct”
Etymology: [L. succinctus, p.p. of succingere to gird below or from below, to tuck up; sub + cingere to gird. Cf. Cincture.]
1. Girded or tucked up; bound; drawn tightly together. His habit fit for speed succinct. Milton.
2. Compressed into a narrow compass; brief; concise. Let all your precepts be succinct and clear. Roscommon. The shortest and most succinct model that ever grasped all the needs and necessities of mankind. South.
Syn. -- Short; brief; concise; summary; compendious; laconic; terse. -- Suc*cinct"ly, adv. -- Suc*cinct"ness, n.
Shades of meaning
Fernald lists succinctness only as an antonym, under circumlocution.
He lists it without comment; the entries above explain its neighbors.