Boyd’s Bible Dictionary:

(sickle shaped). Prominent Jewish musical instrument, invented by Jubal (Gen. 4:2121And his brother's name was Jubal: he was the father of all such as handle the harp and organ. (Genesis 4:21)); of various shapes and sizes; different number of strings; played with fingers or plectrum (quill).

Concise Bible Dictionary:

Egyptian Harp
Musical instrument, probably somewhat like those now bearing the name, for such are seen depicted on the Egyptian monuments. The harp is mentioned as early as Genesis 21. It was one of the instruments used in the temple service (1 Kings 10:1212And the king made of the almug trees pillars for the house of the Lord, and for the king's house, harps also and psalteries for singers: there came no such almug trees, nor were seen unto this day. (1 Kings 10:12); 1 Chron. 13:88And David and all Israel played before God with all their might, and with singing, and with harps, and with psalteries, and with timbrels, and with cymbals, and with trumpets. (1 Chronicles 13:8)). The harp is remarkable for its soft, soothing sounds. It was used by David to drive away the evil spirit from Saul (1 Sam. 16:2323And it came to pass, when the evil spirit from God was upon Saul, that David took an harp, and played with his hand: so Saul was refreshed, and was well, and the evil spirit departed from him. (1 Samuel 16:23)); and it is the only musical instrument referred to symbolically as being in heaven (Rev. 5:88And when he had taken the book, the four beasts and four and twenty elders fell down before the Lamb, having every one of them harps, and golden vials full of odors, which are the prayers of saints. (Revelation 5:8); Rev. 14:22And I heard a voice from heaven, as the voice of many waters, and as the voice of a great thunder: and I heard the voice of harpers harping with their harps: (Revelation 14:2)): called “the harps of God” in Revelation 15:22And I saw as it were a sea of glass mingled with fire: and them that had gotten the victory over the beast, and over his image, and over his mark, and over the number of his name, stand on the sea of glass, having the harps of God. (Revelation 15:2).

Strong’s Dictionary of Hebrew Words:

from a unused root meaning to twang; a harp
KJV Usage:

From Manners and Customs of the Bible:

1. The word toph, here and in other places rendered “tabret,” and in a number of texts translated “timbrel,” represents a very ancient musical instrument of percussion. There are three varieties depicted on the Egyptian monuments: one circular, another square or oblong, and a third consisting of two squares separated by a bar. Over these frames parchment was stretched, and in the rim were small bells or pieces of tinkling brass. The toph was used on occasions of joy, and was generally played by women, and often accompanied by dancing. It is reproduced in the “tambourine” which is occasionally seen in the streets of our large cities in the hands of itinerant musicians as an accompaniment to the barrel-organ.
2. The word kinnor, which frequently occurs in the Old Testament, and is translated “harp,” has given rise to considerable discussion. It was undoubtedly the earliest musical instrument made (Gen. 4:2121And his brother's name was Jubal: he was the father of all such as handle the harp and organ. (Genesis 4:21)), though some suppose that the text referred to is meant to show that Jubal was the inventor of stringed instruments generally, without referring to any particular kind. As to the shape of this ancient instrument there is no certainty. It has been variously represented by different writers as shaped like the lyre, the Greek letter 4, the guitar, and the modern harp. There is equal variety of opinion as to the number of strings. Seven, ten, twenty-four, and forty-seven have been named. It has also been asserted by some that it was played by means of a plectrum, while others assert that it was played by hand. These conflicting statements may all be harmonized by supposing that the shape varied at different times, or that the word kinnor was the generic term for all instruments of the lyre kind; that the number of strings varied at different periods, or with the size of the instrument; that the instruments were of different sizes; and that they were sometimes played with a plectrum and sometimes by hand. The kinnor was a very popular instrument with the Hebrews, and was used at jubilees and festivals. Its use was also practiced by other nations.