Aetiology (αιτιολογια): This is the doctrine and/or study of causes and origins, such as that of creation. “Aitia” (αιτια) meaning cause, and “logos” (λογος) meaning word or study. This term is rarely, if ever, used in theological circles, but if you ever hear it, you know what it means.
Angelology (αγγελολογια): This is the doctrine and/or study of angels. “Angelos” (αγγελος) meaning angel, and “logos” (λογος) meaning word or study.
Anthropology (ανθρωπολογια): This is the doctrine and/or study of mankind. “Anthropos” (ανθρωπος) meaning man, and “logos” (λογος) meaning word or study.
Bibliology (βιβλιολογια): This is the doctrine and/or study of the Bible. “Biblos” (βιβλος) meaning papyrus or scroll (book, essentially), and “logos” (λογος) meaning word or study.
Christology (χριστολογια): This is the doctrine and/or study of Jesus Christ. “Christos” (χριστος) meaning Christ or annointed, and “logos” (λογος) meaning word or study.
Ecclesiology (εκκλησιολογια): This is the doctrine and/or study of the church. “Ecclesia” (εκκλησια) meaning assembly, congregation, or church, and “logos” (λογος) meaning word or study.
Epistemology (επισταμολογια): This is the doctrine and/or study of knowledge. “Epistamai” (επισταμαι) meaning knowledge, and “logos” (λογος) meaning word or study.
Eschatology (εσχατολογια): This is the doctrine and/or study of last things or the end times. “Eschatos” (εσχατος) meaning last or final, and “logos” (λογος) meaning word or study.
Hagiology (αγιολογια): This is defined as "literature dealing with the lives and legends of saints." No doubt this definition and the doctrine resulting thereof comes from the Roman Catholic Church. However, since “hagios” (αγιος) means holy, and “logos” (λογος) means word or study, the more appropriate definition would be the doctrine and/or study of holiness. I have never seen this term used in any systematic theology, but it should be, and with the definition I have given it.
Hamartiology (αμαρτωλογια): This is the doctrine and/or study of sin. “Hamartia” (αμαρτια) meaning to miss the mark, and “logos” (λογος) meaning word or study.
Missiology: This is the doctrine and/or study of missions. “Missio” from mission, and “logos” (λογος) meaning word or study. I believe this term is fairly new in use. Its first root word is also the only Latin word used in all of our "ologies."
Ontology (οντολογια): This is the doctrine and/or study of the nature of being (existence), reality, and substance. “Ontos” (οντος) meaning being, and “logos” (λογος) meaning word or study.
Ouranology (ουρανολογια): This is the doctrine and/or study of heaven. “Ouranos” (ουρανος) meaning heaven, and “logos” (λογος) meaning word or study.
Pneumatology (πνευματολογια): This is the doctrine and/or study of the Holy Spirit. “Pneuma” (πνευμα) meaning wind or spirit, and “logos” (λογος) meaning word or study.
Soteriology (σωτηρολογια): This is the doctrine and/or study of salvation. “Soteria” (σωτηρια) meaning salvation, and “logos” (λογος) meaning word or study.
Theology (θεολογια): This is the doctrine and/or study of God. “Theos” (θεος) meaning God, and “logos” (λογος) meaning word or study.
Angelology (αγγελολογια): This is the doctrine and/or study of angels. “Angelos” (αγγελος) meaning angel, and “logos” (λογος) meaning word or study.
Anthropology (ανθρωπολογια): This is the doctrine and/or study of mankind. “Anthropos” (ανθρωπος) meaning man, and “logos” (λογος) meaning word or study.
Bibliology (βιβλιολογια): This is the doctrine and/or study of the Bible. “Biblos” (βιβλος) meaning papyrus or scroll (book, essentially), and “logos” (λογος) meaning word or study.
Christology (χριστολογια): This is the doctrine and/or study of Jesus Christ. “Christos” (χριστος) meaning Christ or annointed, and “logos” (λογος) meaning word or study.
Ecclesiology (εκκλησιολογια): This is the doctrine and/or study of the church. “Ecclesia” (εκκλησια) meaning assembly, congregation, or church, and “logos” (λογος) meaning word or study.
Epistemology (επισταμολογια): This is the doctrine and/or study of knowledge. “Epistamai” (επισταμαι) meaning knowledge, and “logos” (λογος) meaning word or study.
Eschatology (εσχατολογια): This is the doctrine and/or study of last things or the end times. “Eschatos” (εσχατος) meaning last or final, and “logos” (λογος) meaning word or study.
Hagiology (αγιολογια): This is defined as "literature dealing with the lives and legends of saints." No doubt this definition and the doctrine resulting thereof comes from the Roman Catholic Church. However, since “hagios” (αγιος) means holy, and “logos” (λογος) means word or study, the more appropriate definition would be the doctrine and/or study of holiness. I have never seen this term used in any systematic theology, but it should be, and with the definition I have given it.
Hamartiology (αμαρτωλογια): This is the doctrine and/or study of sin. “Hamartia” (αμαρτια) meaning to miss the mark, and “logos” (λογος) meaning word or study.
Missiology: This is the doctrine and/or study of missions. “Missio” from mission, and “logos” (λογος) meaning word or study. I believe this term is fairly new in use. Its first root word is also the only Latin word used in all of our "ologies."
Ontology (οντολογια): This is the doctrine and/or study of the nature of being (existence), reality, and substance. “Ontos” (οντος) meaning being, and “logos” (λογος) meaning word or study.
Ouranology (ουρανολογια): This is the doctrine and/or study of heaven. “Ouranos” (ουρανος) meaning heaven, and “logos” (λογος) meaning word or study.
Pneumatology (πνευματολογια): This is the doctrine and/or study of the Holy Spirit. “Pneuma” (πνευμα) meaning wind or spirit, and “logos” (λογος) meaning word or study.
Soteriology (σωτηρολογια): This is the doctrine and/or study of salvation. “Soteria” (σωτηρια) meaning salvation, and “logos” (λογος) meaning word or study.
Theology (θεολογια): This is the doctrine and/or study of God. “Theos” (θεος) meaning God, and “logos” (λογος) meaning word or study.