better (adj., adv.)

Old English bettra, earlier betera "of superior quality or excellence," from Proto-Germanic *batizo-, perhaps from PIE *bhad- "good," but Boutkan finds no good IE etymology. For etymology and evolution, see best. Cognate words also have become the comparative adjective of good in the older Germanic languages (Old Frisian betera, Old Saxon betiro, Old Norse betr, Danish bedre, Old High German bezziro, German besser, Gothic batiza). All are comparatives of a positive (Proto-Germanic *bat) which is not in use.

In Middle English the adverbial form commonly was bet, sometimes also was an adjective; bet was displaced by c. 1600. From late Old English as "improved in health, more healthy" (adv.); from late 12c. as "more useful or desirable." Better half "wife" is first attested 1570s.

better (n.1)

late 12c., "that which is better," from better (adj.). Specific meaning "one's superior" is from early 14c. The better "improvement" (as in for the better) is from 1690s. To get the better of someone "obtain mastery or victory over" is from 1650s, from better in a sense of "superiority, mastery," which is recorded from mid-15c. Related: Betters.

better (v.)

Old English *beterian "improve, amend, make better," from Proto-Germanic *batizojan (source also of Old Frisian beteria, Dutch beteren, Old Norse betra, Old High German baziron, German bessern), from *batizo- (see better (adj.)). Meaning "exceed, surpass, outdo" is from 1540s. Related: Bettered; bettering.

better (n.2)

"one who lays wagers;" see bettor.

Definitions of better
better (n.)
something superior in quality or condition or effect;
a change for the better
better (n.)
someone who bets;
Synonyms: bettor / wagerer / punter
better (n.)
a superior person having claim to precedence;
the common man has been kept in his place by his betters
better (n.)
the superior one of two alternatives;
chose the better of the two
better (adj.)
(comparative and superlative of `well') wiser or more advantageous and hence advisable;
it would be better to speak to him
Synonyms: best
better (adj.)
(comparative of `good') superior to another (of the same class or set or kind) in excellence or quality or desirability or suitability; more highly skilled than another;
produced a better mousetrap
she's better in math than in history
a better chance of success
a better type of car
You're a better man than I am, Gunga Din
a better coat
a suit with a better fit
better (adj.)
(comparative of `good') changed for the better in health or fitness;
her health is better now
I feel better
better (adj.)
more than half;
argued for the better part of an hour
better (v.)
surpass in excellence;
She bettered her own record
Synonyms: break
better (v.)
to make better;
better (v.)
get better;
better (adv.)
comparative of `well'; in a better or more excellent manner or more advantageously or attractively or to a greater degree etc.;
a deed better left undone
better suited to the job
She had never sung better
better (adv.)
from a position of superiority or authority;
I know better.
Synonyms: best