From BiblePortal Wikipedia

Hastings' Dictionary of the Bible [1]

MELONS ( ‘ÇŽbattîhîm , the same word as the Arab. [Note: Arabic.] battîkh , which includes the water-melon ( Citrullus vulgaris ) as well as other kinds).   Numbers 11:6 . Here the water-melon is specially referred to, as it was common in Egypt in ancient times. No fruit is more appreciated in the arid wilderness. Melons flourish in Palestine, especially on the sands S. of Jaffa, and are eaten all over the land, being carried to the towns all through the summer by long strings of camels.

E. W. G. Masterman.

Smith's Bible Dictionary [2]

Melons. (Hebrew, abattichim ). Melons are mentioned only in  Numbers 11:5. By the Hebrew word, we are probably to understand both the melon, ( Cumcumis melo ) and the watermelon, ( Cucurbita citrullus ). The watermelon, which is now extensively cultivated in all hot countries, is a fruit, not unlike the common melon, but the leaves are deeply lobed and gashed; the flesh is pink or white, and contains a large quantity of cold watery juice with out much flavor; the seeds are black.

Morrish Bible Dictionary [3]

abattichim. The similar Arabic word batekh is a generic name for melons, etc., and would include different species. The common melon in the East is the cucumis melo , and the water melon the cucurbita citrullus. The melon was one of the fruits the Israelites had eaten in Egypt, and for which they longed in the wilderness.   Numbers 11:5 . Kitto long remembered the gratitude with which he received a slice of melon when travelling in a hot and dry plainin the East.

American Tract Society Bible Dictionary [4]

Are common in the East, but do not differ particularly form ours. Watermelons grow luxuriantly in Palestine, even in dry and sandy soil. They are a delicious fruit in a hot climate, and were among the articles of food for which the Hebrews pined in the desert,  Numbers 11:5 .

People's Dictionary of the Bible [5]

Melons.  Numbers 11:5. Melons of all kinds have ever been largely cultivated in Egypt, and in summer often form the chief food and drink of the lower classes.

Holman Bible Dictionary [6]

Plants In The Bible

Easton's Bible Dictionary [7]

 Numbers 11:5

International Standard Bible Encyclopedia [8]

mel´unz ( אבטּחים , 'ăbhaṭṭı̄ḥı̄m  ; compare Arabic battikh , the "water melon"; πέπονες , pépones ): In   Numbers 11:5 , the melon is referred to as common in Egypt, and there can be no doubt that the variety indicated is the watermelon ( Citrullus vulgaris ) which is indigenous in tropical Africa. It has been cultivated in Egypt since the earliest times.