'Bigger' definitions:

Definition of 'bigger'

adjective

Large or big relative to something else [syn: bigger, larger]

From: GCIDE

Big \Big\ (b[i^]g), a. [Compar. Bigger; superl. Biggest.] [Perh. from Celtic; cf. W. beichiog, beichiawg, pregnant, with child, fr. baich burden, Arm. beac'h; or cf. OE. bygly, Icel. biggiligr, (properly) habitable; (then) magnigicent, excellent, fr. OE. biggen, Icel. byggja, to dwell, build, akin to E. be.]
1. Having largeness of size; of much bulk or magnitude; of great size; large. "He's too big to go in there." --Shak. [1913 Webster]
2. Great with young; pregnant; swelling; ready to give birth or produce; -- often figuratively. [1913 Webster]
[Day] big with the fate of Cato and of Rome. --Addison. [1913 Webster]
3. Having greatness, fullness, importance, inflation, distention, etc., whether in a good or a bad sense; as, a big heart; a big voice; big looks; to look big. As applied to looks, it indicates haughtiness or pride. [1913 Webster]
God hath not in heaven a bigger argument. --Jer. Taylor. [1913 Webster]
Note: Big is often used in self-explaining compounds; as, big-boned; big-sounding; big-named; big-voiced. [1913 Webster]
To talk big, to talk loudly, arrogantly, or pretentiously. [1913 Webster]
I talked big to them at first. --De Foe. [1913 Webster]
Syn: Bulky; large; great; massive; gross. [1913 Webster] Big

From: GCIDE