Vine's Expository Dictionary of New Testament.

John 14:16.
And I will pray the Father, and he shall give you *another* Comforter, that he may abide with you for ever; 

Topic: Another

<1,,243 2087,allos heteros> 
have a difference in meaning, which despite a tendency to be lost, is to be observed in numerous passages. Allos expresses a numerical difference and denotes "another of the same sort;" heteros expresses a qualitative difference and denotes "another of a different sort." Christ promised to send "another Comforter" (allos, "another like Himself," not heteros), John 14:16. Paul says "I see a different (AV, "another") law," heteros, a law different from that of the spirit of life (not allos, "a law of the same sort"), Rom. 7:23. After Joseph's death "another king arose," heteros, one of quite a different character, Acts 7:18. Paul speaks of "a different gospel (heteros), which is not another" (allos, another like the one he preached), Gal. 1:6,7. See heteros (not allos) in Matt. 11:3; Acts 27:1; in Luke 23:32 heteroi is used of the two malefactors crucified with Christ. The two words are only apparently interchanged in 1 Cor. 1:16; 6:1; 12:8-10; 14:17,19, e.g., the difference being present, though not so readily discernible. 

They are not interchangeable in 1 Cor. 15:39-41; here heteros is used to distinguish the heavenly glory from the earthly, for these differ in genus, and allos to distinguish the flesh of men, birds, and fishes, which in each case is flesh differing not in genus but in species. Allos is used again to distinguish between the glories of the heavenly bodies, for these also differ not in kind but in degree only. For allos, see MORE, OTHER, etc. For heteros, see OTHER, STRANGE. 

Note: The distinction comes out in the compounds of heteros, viz., heteroglossos, "strange tongues," 1 Cor. 14:21; heterodidaskaleo, "to teach a different doctrine," 1 Tim. 1:3; 6:3; heterozugo, "to be unequally yoked" (i.e., with those of a different character), 2 Cor. 6:14.

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 Topic: First-begotten, Firstborn

<1,,4416,prototokos> 
"firstborn" (from protos, "first," and tikto, "to beget"), is used of Christ as born of the Virgin Mary, Luke 2:7; further, in His relationship to the Father, expressing His priority to, and preeminence over, creation, not in the sense of being the "first" to be born. It is used *occasionally* of superiority of position in the OT; see Exod. 4:22; Deut. 21:16,17, the prohibition being against the evil of assigning the privileged position of the "firstborn" to one born subsequently to the "first" child. 

The five passages in the NT relating to Christ may be set forth chronologically thus: (a) Col. 1:15, where His eternal relationship with the Father is in view, and the clause means both that He was the "Firstborn" before all creation and that He Himself produced creation (the genitive case being objective, as ver. 16 makes clear); (b) Col. 1:18; Rev. 1:5, in reference to His resurrection; (c) Rom. 8:29, His position in relationship to the church; (d) Heb. 1:6, RV, His Second Advent (the RV "when He again bringeth in," puts "again" in the right place, the contrast to His First Advent, at His birth, being implied); cp. Ps. 89:27: The word is used in the plural, in Heb. 11:28, of the firstborn sons in the families of the Egyptians, and in Ps. 12:23, of the members of the Church. 

Note: With (a) cp. John 1:30, "He was before me," lit., "He was first (protos) of me," i.e., "in regard to me," expressing all that is involved in His preexistence and priority.