cut down, lament, mourn, (be-)wail

Boyd’s Bible Dictionary:

Very public and demonstrative
(Gen. 23:2; 37:29-352And Sarah died in Kirjath-arba; the same is Hebron in the land of Canaan: and Abraham came to mourn for Sarah, and to weep for her. (Genesis 23:2)
29And Reuben returned unto the pit; and, behold, Joseph was not in the pit; and he rent his clothes. 30And he returned unto his brethren, and said, The child is not; and I, whither shall I go? 31And they took Joseph's coat, and killed a kid of the goats, and dipped the coat in the blood; 32And they sent the coat of many colors, and they brought it to their father; and said, This have we found: know now whether it be thy son's coat or no. 33And he knew it, and said, It is my son's coat; an evil beast hath devoured him; Joseph is without doubt rent in pieces. 34And Jacob rent his clothes, and put sackcloth upon his loins, and mourned for his son many days. 35And all his sons and all his daughters rose up to comfort him; but he refused to be comforted; and he said, For I will go down into the grave unto my son mourning. Thus his father wept for him. (Genesis 37:29‑35)). Period, seven to seventy days (Gen. 1:33And God said, Let there be light: and there was light. (Genesis 1:3); 1 Sam. 31:1313And they took their bones, and buried them under a tree at Jabesh, and fasted seven days. (1 Samuel 31:13)). Hired mourners (EccL 12:5; Matt. 9:2323And when Jesus came into the ruler's house, and saw the minstrels and the people making a noise, (Matthew 9:23)). Methods, weeping, tearing clothes, wearing sackcloth, sprinkling with ashes or dust, shaving head, plucking beard, fasting, laceration.

Concise Bible Dictionary:

It was the habit of the Hebrews, as it still is in the East, to make a great demonstration of their mourning. They would beat their breasts, cover their heads, fast, put dust and ashes on their heads, neglect their hair, wear dull-colored garments, rend their clothes, wear sackcloth, and so forth. For Asa and Zedekiah there was “great burning” of odors at their death, which was most probably copied from the heathen (2 Chron. 16:1414And they buried him in his own sepulchres, which he had made for himself in the city of David, and laid him in the bed which was filled with sweet odors and divers kinds of spices prepared by the apothecaries' art: and they made a very great burning for him. (2 Chronicles 16:14); Jer. 34:55But thou shalt die in peace: and with the burnings of thy fathers, the former kings which were before thee, so shall they burn odors for thee; and they will lament thee, saying, Ah lord! for I have pronounced the word, saith the Lord. (Jeremiah 34:5)). At a death professional mourners were hired, mostly women. “Call for the mourning women.... let them make haste, and take up a wailing for us, that our eyes may run down with tears, and our eyelids gush out with waters” (Jer. 9:17-1817Thus saith the Lord of hosts, Consider ye, and call for the mourning women, that they may come; and send for cunning women, that they may come: 18And let them make haste, and take up a wailing for us, that our eyes may run down with tears, and our eyelids gush out with waters. (Jeremiah 9:17‑18); compare 2 Sam. 14:22And Joab sent to Tekoah, and fetched thence a wise woman, and said unto her, I pray thee, feign thyself to be a mourner, and put on now mourning apparel, and anoint not thyself with oil, but be as a woman that had a long time mourned for the dead: (2 Samuel 14:2); Amos 5:1616Therefore the Lord, the God of hosts, the Lord, saith thus; Wailing shall be in all streets; and they shall say in all the highways, Alas! alas! and they shall call the husbandman to mourning, and such as are skilful of lamentation to wailing. (Amos 5:16)). Musicians also attended at deaths, who played mournful strains (Matt. 9:2323And when Jesus came into the ruler's house, and saw the minstrels and the people making a noise, (Matthew 9:23)). God does not desire those who are bereaved to be without feeling: the Lord wept at the grave of Lazarus, but He would have reality in all things. He had to say to His people, “Rend your heart, and not your garments” (Joel 2:1313And rend your heart, and not your garments, and turn unto the Lord your God: for he is gracious and merciful, slow to anger, and of great kindness, and repenteth him of the evil. (Joel 2:13)).

Strong’s Dictionary of Greek Words:

Number:
2875 (find all occurrences in KJV Bible)
Greek:
κόπτω
Transliteration:
kopto
Phonic:
kop’-to
Meaning:
a primary verb; to "chop"; specially, to beat the breast in grief
KJV Usage:
cut down, lament, mourn, (be-)wail. Compare the base of 5114

From Manners and Customs of the Bible:

Rending the clothes as a token of grief is a very ancient custom, and is often referred to in the Bible. See Joshua 7:66And Joshua rent his clothes, and fell to the earth upon his face before the ark of the Lord until the eventide, he and the elders of Israel, and put dust upon their heads. (Joshua 7:6); 1 Samuel 4:1212And there ran a man of Benjamin out of the army, and came to Shiloh the same day with his clothes rent, and with earth upon his head. (1 Samuel 4:12); 2 Samuel 1:11; 3:31; 13:3111Then David took hold on his clothes, and rent them; and likewise all the men that were with him: (2 Samuel 1:11)
31And David said to Joab, and to all the people that were with him, Rend your clothes, and gird you with sackcloth, and mourn before Abner. And king David himself followed the bier. (2 Samuel 3:31)
31Then the king arose, and tare his garments, and lay on the earth; and all his servants stood by with their clothes rent. (2 Samuel 13:31); 2 Kings 2:12; 18:37; 19:112And Elisha saw it, and he cried, My father, my father, the chariot of Israel, and the horsemen thereof. And he saw him no more: and he took hold of his own clothes, and rent them in two pieces. (2 Kings 2:12)
37Then came Eliakim the son of Hilkiah, which was over the household, and Shebna the scribe, and Joah the son of Asaph the recorder, to Hezekiah with their clothes rent, and told him the words of Rabshakeh. (2 Kings 18:37)
1And it came to pass, when king Hezekiah heard it, that he rent his clothes, and covered himself with sackcloth, and went into the house of the Lord. (2 Kings 19:1); Ezra 9:33And when I heard this thing, I rent my garment and my mantle, and plucked off the hair of my head and of my beard, and sat down astonied. (Ezra 9:3); Job 1:2020Then Job arose, and rent his mantle, and shaved his head, and fell down upon the ground, and worshipped, (Job 1:20). A Jewish writer, quoted by Brinier, says that this ceremony was performed in the following mariner: “They take a knife, and holding the blade downward, do give the upper garment a cut on the right side, and then rend it a hand’s breadth. This is done for the five following relations, brother, sister, son, daughter, or wife; but for father or mother the rent is on the left side, and in all the garments” (Oriental Customs, No. 65).
Sackcloth is also frequently mentioned. It was generally made of the hair of goats or of camels, and was coarse and black. It was used for straining liquids, for sacks, and for mourning garments. When used for mourning it was sometimes worn next to the skin, which it must have chafed by its harshness, and at other times it was hung like a sack over the outer garments, or instead of them. A girdle of similar material confined its loose folds. Ahab, on one occasion, appears to have worn sackcloth next to his skin all night. See 1 Kings 21:2727And it came to pass, when Ahab heard those words, that he rent his clothes, and put sackcloth upon his flesh, and fasted, and lay in sackcloth, and went softly. (1 Kings 21:27). In Revelation 6:1212And I beheld when he had opened the sixth seal, and, lo, there was a great earthquake; and the sun became black as sackcloth of hair, and the moon became as blood; (Revelation 6:12), in the darkness accompanying an earthquake, the sun is said to have become as “black as sackcloth of hair.”