put to death, kill, (man-)slay(-er), murder(-er)

“Murder” From Boyd’s Bible Dictionary:

(death). Punished with death (Ex. 21:1212He that smiteth a man, so that he die, shall be surely put to death. (Exodus 21:12); Num. 35:30-3130Whoso killeth any person, the murderer shall be put to death by the mouth of witnesses: but one witness shall not testify against any person to cause him to die. 31Moreover ye shall take no satisfaction for the life of a murderer, which is guilty of death: but he shall be surely put to death. (Numbers 35:30‑31)); but cities of refuge provided for the escape of the involuntary slayer (Ex. 21:1313And if a man lie not in wait, but God deliver him into his hand; then I will appoint thee a place whither he shall flee. (Exodus 21:13); Num. 35:3232And ye shall take no satisfaction for him that is fled to the city of his refuge, that he should come again to dwell in the land, until the death of the priest. (Numbers 35:32); Deut. 19:1-131When the Lord thy God hath cut off the nations, whose land the Lord thy God giveth thee, and thou succeedest them, and dwellest in their cities, and in their houses; 2Thou shalt separate three cities for thee in the midst of thy land, which the Lord thy God giveth thee to possess it. 3Thou shalt prepare thee a way, and divide the coasts of thy land, which the Lord thy God giveth thee to inherit, into three parts, that every slayer may flee thither. 4And this is the case of the slayer, which shall flee thither, that he may live: Whoso killeth his neighbor ignorantly, whom he hated not in time past; 5As when a man goeth into the wood with his neighbor to hew wood, and his hand fetcheth a stroke with the axe to cut down the tree, and the head slippeth from the helve, and lighteth upon his neighbor, that he die; he shall flee unto one of those cities, and live: 6Lest the avenger of the blood pursue the slayer, while his heart is hot, and overtake him, because the way is long, and slay him; whereas he was not worthy of death, inasmuch as he hated him not in time past. 7Wherefore I command thee, saying, Thou shalt separate three cities for thee. 8And if the Lord thy God enlarge thy coast, as he hath sworn unto thy fathers, and give thee all the land which he promised to give unto thy fathers; 9If thou shalt keep all these commandments to do them, which I command thee this day, to love the Lord thy God, and to walk ever in his ways; then shalt thou add three cities more for thee, beside these three: 10That innocent blood be not shed in thy land, which the Lord thy God giveth thee for an inheritance, and so blood be upon thee. 11But if any man hate his neighbor, and lie in wait for him, and rise up against him, and smite him mortally that he die, and fleeth into one of these cities: 12Then the elders of his city shall send and fetch him thence, and deliver him into the hand of the avenger of blood, that he may die. 13Thine eye shall not pity him, but thou shalt put away the guilt of innocent blood from Israel, that it may go well with thee. (Deuteronomy 19:1‑13)).

“38. Murderer. Manslayer. Assassin” From Concise Bible Dictionary:

ἀνθρωποκτόνος. (from ἄνθρωππς,man,' and κτείνω,to slay' agrees more with our word ‘man-slayer,' and is applied when murder may not have been committed. "Whosoever hateth his brother is a murderer: and ye know that no murderer hath eternal life abiding in him." 1 John 3:1515Whosoever hateth his brother is a murderer: and ye know that no murderer hath eternal life abiding in him. (1 John 3:15). The devil "was a murderer [mansleer, Wickliffe] from the beginning." John 8:4444Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it. (John 8:44). This word serves to bring into contrast the slaying of MAN, and eternal life for man through our Lord Jesus Christ.
σικάιος (the Latin sicarius) is so called from sica, a short dagger or poniard. There was a secret society called Sicarii, the members of which carried daggers under their garments, and killed any who opposed them. Perhaps ‘assassin' is the best equivalent. It occurs only in Acts 21:3838Art not thou that Egyptian, which before these days madest an uproar, and leddest out into the wilderness four thousand men that were murderers? (Acts 21:38).

“Man-Slayer” From Concise Bible Dictionary:

See AVENGER.

“Murder” From Concise Bible Dictionary:

The first death was caused by murder when Cain slew his brother Abel, and the second recorded is when Lamech said, “I have slain a man to my wounding,” or “for my wound”; which may mean that he did it in self-defense (Gen. 4:2323And Lamech said unto his wives, Adah and Zillah, Hear my voice; ye wives of Lamech, hearken unto my speech: for I have slain a man to my wounding, and a young man to my hurt. (Genesis 4:23)). God set a mark upon Cain that none should kill him; and Lamech said, “If Cain shall be avenged sevenfold, truly Lamech seventy and sevenfold.” After the flood God made a definite law concerning murder. God would require expiation for the blood of man, whether it was shed by beast or by man; at the hand of every man’s brother, or kinsman, God would require the life of man. “Whoso sheddeth man’s blood, by man shall his blood be shed: for in the image of God made He man” (Gen. 9:5-65And surely your blood of your lives will I require; at the hand of every beast will I require it, and at the hand of man; at the hand of every man's brother will I require the life of man. 6Whoso sheddeth man's blood, by man shall his blood be shed: for in the image of God made he man. (Genesis 9:5‑6)). This injunction was repeated in the law, and has never been rescinded or modified. Neither does the New Testament in any way alter it: indeed it incidentally confirms it by declaring that the magistrate does not bear the sword in vain (Rom. 13:44For he is the minister of God to thee for good. But if thou do that which is evil, be afraid; for he beareth not the sword in vain: for he is the minister of God, a revenger to execute wrath upon him that doeth evil. (Romans 13:4)). God claims the life of man, and none can set aside His rights.

Strong’s Dictionary of Hebrew Words:

Transliteration:
ratsach
Phonic:
raw-tsakh’
Meaning:
a primitive root; properly, to dash in pieces, i.e. kill (a human being), especially to murder
KJV Usage:
put to death, kill, (man-)slay(-er), murder(-er)