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Watson's Biblical & Theological Dictionary [1]

and JAMBRES, or, as Pliny calls them, Jamne and Jotape, two magicians, who resisted Moses in Egypt,  2 Timothy 3:8 . He speaks, likewise, of the faction or sect of magicians, of which, he says, Moses, Jannes, and Jocabel, or Jopata, were heads. By this last word he meant probably the patriarch Joseph. whom the Egyptians considered as one of their most celebrated sages. The Mussulmans have several particulars to the same purpose. The paraphrast Jonathan says they were the sons of Balaam, who accompanied him to Balak, king of Moab. They are called by several names in several translations; by the Septuagint, φαρμακι , poisoners, and επαοιδοι , enchanters; by Sulpitius Severus, Chaldaeans, that is, astrologers; by others, sapientes and malefici, wise men, that is, so esteemed among the Egyptians, philosophers, and witches. Artapanus tells us, that Pharaoh sent for magicians from Upper Egypt to oppose Moses. Ambrosiaster, or Hilary, the deacon, says they were brothers. He cites a book entitled "Jannes and Mambres," which is likewise quoted by Origen, and ranked as apocryphal by Pope Gelasius. Some of the Hebrews call them Janes and Jambres; others, Jochana and Mamre, or Jonas and Jombros. Jerom translates their names Johannes and Mambres; and there is a tradition, they say, in the Talmud, that Juhanni and Mamre, chief of Pharaoh's physicians, said to Moses, "Thou bringest straw into Egypt, where abundance of corn grew;" that is, to bring your magical arts hither is to as much purpose as to bring water to the Nile. Some say their names are the same as John and Ambrose. Some will have it that they fled away with their father; others, that they were drowned in the Red Sea with the Egyptians; others, that they were killed by Phinehas in the war against the Midianites. Numenius, cited by Aristobulus, says that Jannes and Jambres were sacred tribes of the Egyptians, who excelled in magic at the time when the Jews were driven out of Egypt. See Plagues Of Egypt .

Smith's Bible Dictionary [2]

Jan'nes. Jan'nes and Jam'bres , the names of two Egyptian magicians who opposed Moses.  Exodus 7:9-13;  2 Timothy 3:8-9. (B.C. 1492).

American Tract Society Bible Dictionary [3]

And  Exodus 7:11 , etc. These names are not found in the Old Testament, but are often mentioned in the rabbinical books,  2 Timothy 3:8 .

Easton's Bible Dictionary [4]

 2 Timothy 3:8

Hawker's Poor Man's Concordance And Dictionary [5]

See Jambres

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [6]

( Ι᾿Αννῆς , probably of Egyptian etymology [see below]). Jannes and Jambres are thought to have been two of the Egyptiani magicians who attempted by their enchantments ( לָטַים ,  Exodus 7:22, etc.; or לְהָטַים ,  Exodus 7:11, Secret Arts) to counteract the influence on Pharaoh's mind of the miracles wrought by Moses (see Exodus 7, 8). Their names occur nowhere in the Hebrew Scriptures, and only once in the New Testament ( 2 Timothy 3:8), where Paul says no more than that they "withstood Moses," and that their folly in doing so became manifest ( 2 Timothy 3:8-9). He became acquainted with them, most probably, from an ancient Jewish tradition, or, as Theodoret expresses it, "from the unwritten teaching of the Jews." They are found frequently in the Talmudical and Rabbinical writings but with some variations. Thus, for Jannes we meet with יניס יונוס יואני יוחני יוחנא . Of these, the last three are forms of the Hebrew יוחנן , which has led to the supposition that Ι᾿Αννῆς is a contracted form of the Greek Ι᾿Ωάννης . Some critics (Pfeiffer, Dub. Vex. 1, 253) consider these names to be of Egyptian origin, and in that case the Jewish writers must have been misled by a similarity of sound to adopt the forms above mentioned, as the Mishna (Sanhedr. 98, b; Chol. 19, a) has done in the case of other unknown proper names (Majus, Observat. sacr. 2, 42). For Jambres we find ממרי ממרא יומברוס ימבריס , and in the Shalsheleth Hakkabala (13, 2) the two names are given ואמברוטיאו יואני , i.e. Johannes and Ambrosius!

The Targum of Jonathan inserts them in  Exodus 2:11. The same writer also gives as a reason for Pharaoh's edict for the destruction of the Israelitish male children that "this monarch had a dream in. which the land of Egypt appeared in one scale and a lamb in- another; that on awakening he sought for its interpretation from his wise men; whereupon Jannes and Jambres ( וימבריס יניס ) said, "A son is to be born in the congregation of Israel who will desolate the whole land of Egypt." Several of the Jewish writers speak of Jannes and Jambres as the two sons of Balaam (Talmud, Jalkut Ruben, 81, 3), and assert that they were the youths ( נְעָטָרַים , Auth. Version Servants) who went with him to the king of Moab ( Numbers 22:22). Arabian tradition assigns them a place in Egyptian history (see the Asiatic Journal, 1843, No.. 7, p. 73). Their graves were located in Egypt (Pallad. Lausiac. 20). The Pythagorean philosopher Numenius mentions these persons in a passage preserved by Eusebius (Praeparatio Evang. 9: 8), and by Origen (C. Cels. 4: p. 198, ed. Spencer); also Pliny (Hist. Nat. 30: 1), and apparently Apuleius Apol. p. 94). The Arabs mention the names of several magicians who opposed Moses;. among them is none resembling Jannes and Jambres (D'Herbelot, s.v. Moussa Ben Amran). There was an ancient apocryphal writing entitled Jannes and Mambres, which is referred to by Origen (in Matthew Comment. § 117; Opera, 5, 29), and by Ambrosiaster, or Hilary the Deacon:. it was condemned by pope Gelasius.

Jannes appears to be a transcription of the Egyptian name Annu, probably pronounced Ian. It was the nomen of two kings': one of the eleventh dynasty, the father or ancestor of Sesertesen I of the twelfth; the other, according to our arrangement, fourth or fifth king of the fifteenth dynasty, called by Manetho Ι᾿Άννας or Ι᾿Ανίας (Josephus), or Σταάν (Africanus). See Poole; Horce Egyptiacae, p. 174 sq. There is also a king bearing the name Annu, whom we assign to the second dynasty (Hor. G. p. 101). The significations of Adan is doubtful: the cognate word Aant means a valley or plain. The earlier king Aan may be assigned to the 21st century B.C.; the later one is thought to have been the second predecessor of Joseph's Pharaoh. This shows that a name which may be reasonably supposed to be the original of Jannes was in use at or near the period of the sojourn in Egypt. The names of the ancient Egyptians were extremely. numerous, and very fluctuating in use; generally, the most prevalent at any time were those of kings then reigning or not long dead. See Wetstenii Nov. Test. Graec. 2, 362; Buxtorf, Lex. Talm. Rabb. col. 945; Lightfoot's Sermon on James and Jambres (in Works, 7:89); Erubhin, or Miscellanies, ch. 24 (in Works, 4, 33); Lardner's Credibility, pt. 2, ch. 35 (in Works, 7, 381); Fabric. Pseudepigr. V. T. 1, 813; Thilo, Cod. Apocryph. 1, 553; the dissertations De Janne et Jambre of Zentgrav (Argent. 1699); Grotius (Hafn. 1707); Michaelis (Hal. 1747); and Hermann, De pseudothaumaturgio Pharaonis (Jen. 1745).