"the metaphysical science or study of being and the essence of things," 1660s (Gideon Harvey), from Modern Latin ontologia (c. 1600); see onto- + -logy. Related: Ontologist.
Entries linking to ontology
onto-
word-forming element meaning "a being, individual; being, existence," from stem of Greek on (genitive ontos) "being," neuter present participle of einai "to be" (from PIE root *es- "to be").
-logy
word-forming element meaning "a speaking, discourse, treatise, doctrine, theory, science," from Greek -logia (often via French -logie or Medieval Latin -logia), from -log-, combining form of legein "to speak, tell;" thus, "the character or deportment of one who speaks or treats of (a certain subject);" from PIE root *leg- (1) "to collect, gather," with derivatives meaning "to speak (to 'pick out words')." Often via Medieval Latin -logia, French -logie. In philology "love of learning; love of words or discourse," apology, doxology, analogy, trilogy, etc., Greek logos "word, speech, statement, discourse" is directly concerned.