Vine's Expository Dictionary of NT Words 
from kratos, "strong" (which denotes power in activity and effect), serves as the comparative degree of agathos, "good" (good or fair, intrinsically). Kreisson is especially characteristic of the Epistle to the Hebrews, where it is used 12 times; it indicates what is (a) advantageous or useful, 1—Corinthians 7:9,38; 11:17; Hebrews 11:40; 12:24; 2—Peter 2:21; Philippians 1:23 , where it is coupled with mallon, "more," and pollo, "much, by far," "very far better" (RV); (b) excellent, Hebrews 1:4; 6:9; 7:7,19,22; 8:6; 9:23; 10:34; 11:16,35 .
the neuter of kalos, with mallon, "more," is used in Mark 9:42 , "it were better (lit., 'much better') for him if a great millstone were hanged about his neck." In verses Mark 9:43,45,47 , kalos is used alone (RV, "good," for AV, "better").
King James Dictionary 
BET'TER, a comp. of bet. See Best.
1. Having good qualities in a greater degree than another applied to physical, acquired or moral qualities as a better soil, a better man, a better physician, a better house, a better air, a better harvest. 2. More advantageous.
Were it not better for us to return to Egypt: Exodus 14
3. More acceptable.
To obey is better than sacrifice. 1 Samuel 15
4. More safe.
It is better to trust in the Lord, than to put confidence in man. Psalms 118
5. Improved in health less affected with disease as, the patient is better. 6. To be better off, to be in a better condition. Beddoes,Hygeia. This is a very common phrase but ought not off, to be of? It is not elegant. 7. To have the better, is to have the advantage or superiority, followed by of before him or that over which the advantage is enjoyed as, the English had the better of the Spaniards. 8. To get or gain the better, is to obtain the advantage, superiority or victory as, to get the better of an enemy. 9. For the better, is for the advantage or improvement.
BET'TER, adv. In a more excellent manner with more skill and wisdom, virtue, advantage or success as, to perform work better to plan a scheme better land better cultivated laws better executed government better administered.
1. More correctly, or fully as, to understand a subject better than another. 2. With superior excellence as, to write or speak better than another. 3. With more affection in a higher degree as, to love one better than another.
It is not easy to specify and exemplify the various applications of better. In general,it implies what is more excellent, advantageous, useful, or virtuous, than something else.
1. To improve to meliorate to increase the good qualities of as, manure betters land discipline may better the morals. 2. To surpass to exceed.
The works of nature do always aim at that which cannot be bettered.
Qu.is not the sense, made better:
3. To advance to support to give advantage to as, to better a party to better a cause.
BET'TER, n. A superior one who has a claim to precedence on account of his rank, age, or office as, give place to your betters. It is generally or always used in the plural.
Webster's Dictionary 
(1): (n.) One who has a claim to precedence; a superior, as in merit, social standing, etc.; - usually in the plural.
(2): (compar.) In a superior or more excellent manner; with more skill and wisdom, courage, virtue, advantage, or success; as, Henry writes better than John; veterans fight better than recruits.
(3): (compar.) More correctly or thoroughly.
(4): (a.) Greater in amount; larger; more.
(5): (a.) Improved in health; less affected with disease; as, the patient is better.
(6): (compar.) More, in reference to value, distance, time, etc.; as, ten miles and better.
(7): (a.) More advanced; more perfect; as, upon better acquaintance; a better knowledge of the subject.
(8): (a.) Having good qualities in a greater degree than another; as, a better man; a better physician; a better house; a better air.
(9): (a.) To improve or ameliorate; to increase the good qualities of.
(10): (a.) To improve the condition of, morally, physically, financially, socially, or otherwise.
(11): (v. i.) To become better; to improve.
(12): (a.) To give advantage to; to support; to advance the interest of.
(13): (a.) Preferable in regard to rank, value, use, fitness, acceptableness, safety, or in any other respect.
(14): (n.) One who bets or lays a wager.
(15): (compar.) In a higher or greater degree; more; as, to love one better than another.
(16): (n.) Advantage, superiority, or victory; - usually with of; as, to get the better of an enemy.
(17): (a.) To surpass in excellence; to exceed; to excel.