A — 1: εὐαγγέλιον
(Strong's #2098 — Noun Neuter — euangelion — yoo-ang-ghel'-ee-on )

originally denoted a reward for good tidings; later, the idea of reward dropped, and the word stood for "the good news" itself. The Eng. word "gospel," i.e. "good message," is the equivalent of euangelion (Eng., "evangel"). In the NT it denotes the "good tidings" of the Kingdom of God and of salvation through Christ, to be received by faith, on the basis of His expiatory death, His burial, resurrection, and ascension, e.g., Acts 15:7; 20:24; 1—Peter 4:17 . Apart from those references and those in the Gospels of Matthew and Mark, and Revelation 14:6 , the noun is confined to Paul's Epistles. The Apostle uses it of two associated yet distinct things, (a) of the basic facts of the death, burial and resurrection of Christ, e.g., 1—Corinthians 15:1-3; (b) of the interpretation of these facts, e.g., Romans 2:16; Galatians 1:7,11; 2:2; in (a) the "Gospel" is viewed historically, in (b) doctrinally, with reference to the interpretation of the facts, as is sometimes indicated by the context.

Mark 1:14Romans 1:115:162—Corinthians 11:71—Thessalonians 2:2,91—Peter 4:17Romans 1:1-3Romans 1:9Mark 1:12—Thessalonians 1:8Romans 15:192—Corinthians 4:4Acts 20:241—Timothy 1:11Ephesians 1:13Ephesians 6:15Matthew 4:239:3524:14Revelation 14:6Galatians 2:14Matthew 4:23Galatians 2:2 1—Thessalonians 2:2Acts 20:241—Corinthians 15:12—Corinthians 11:7Galatians 1:11 1—Corinthians 9:14Philippians 2:22Philippians 4:3Romans 15:16Romans 15:192—Timothy 1:82—Corinthians 11:4Romans 10:162—Thessalonians 1:8Mark 1:15Galatians 1:71—Corinthians 9:23
B — 1: εὐαγγελίζω
(Strong's #2097 — Verb — euangelizo — yoo-ang-ghel-id'-zo )

"to bring or announce glad tidings" (Eng., "evangelize"), is used (a) in the Active Voice in Revelation 10:7 ("declared") and Revelation 14:6 ("to proclaim," RV, AV, "to preach"); (b) in the Passive Voice, of matters to be proclaimed as "glad tidings," Luke 16:16; Galatians 1:11; 1—Peter 1:25; of persons to whom the proclamation is made, Matthew 11:5; Luke 7:22; Hebrews 4:2,6; 1—Peter 4:6; (c) in the Middle Voice, especially of the message of salvation, with a personal object, either of the person preached, e.g., Acts 5:42; 11:20; Galatians 1:16 , or, with a preposition, of the persons evangelized, e.g., Acts 13:32 , "declare glad tidings;" Romans 1:15; Galatians 1:8; with an impersonal object, e.g., "the word," Acts 8:4; "good tidings," Acts 8:12; "the word of the Lord," Acts 15:35; "the gospel," 1—Corinthians 15:1; 2—Corinthians 11:7; "the faith," Galatians 1:23; "peace," Ephesians 2:17; "the unsearchable riches of Christ, Ephesians 3:8 . See PREACH , SHEW , TIDINGS.

B — 2: προευαγγελίζομαι
(Strong's #4283 — Verb — proeuangelizomai — pro-yoo-ang-ghel-id'-zom-ahee )

"to announce glad tidings beforehand," is used in Galatians 3:8 .