My better half. A jocose way of saying my wife. As the twain
are one, each is half. Horace calls his friend animæ dimidium meæ.
(1 Odes iii. 8.)
To be better than his word.
To do more than he promised. To think better of the matter.
To give it further consideration; to form a more correct opinion
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894