'Plumper' definitions:

Definition of 'Plumper'

From: GCIDE

Plumper \Plump"er\, n.
1. One who, or that which, plumps or swells out something else; hence, something carried in the mouth to distend the cheeks. [1913 Webster]
2. (English Elections) A vote given to one candidate only, when two or more are to be elected, thus giving him the advantage over the others. A person who gives his vote thus is said to plump, or to plump his vote. [1913 Webster]
3. A voter who plumps his vote. [Eng.] [1913 Webster]
4. A downright, unqualified lie. [Colloq. or Low] [1913 Webster]

From: GCIDE

Plump \Plump\ (pl[u^]mp), a. [Compar. Plumper (pl[u^]mp"[~e]r); superl. Plumpest.] [OE. plomp rude, clumsy; akin to D. plomp, G., Dan., & Sw. plump; probably of imitative origin. Cf. Plump, adv.]
1. Well rounded or filled out; full; fleshy; fat; as, a plump baby; plump cheeks. --Shak. [1913 Webster]
The god of wine did his plump clusters bring. --T. Carew. [1913 Webster]
2. Done or made plump, or suddenly and without reservation; blunt; unreserved; direct; downright.
After the plump statement that the author was at Erceldoune and spake with Thomas. --Saintsbury. [Webster 1913 Suppl.]