- ontology (n.)
- "metaphysical science or study of being," 1660s (Gideon Harvey), from Modern Latin ontologia (c. 1600), from onto- + -logy.
- paleontology (n.)
- 1833, probably from French paléontologie, from Greek palaios "old, ancient" (see paleo-) + ontologie (see ontology). Related: Paleontological.
- ontological (adj.)
- 1782, from ontology + -ical. Related: Ontologically
- gerontology (n.)
- 1903, coined in English from geronto-, used as comb. form of Greek geron (genitive gerontos) "old man," from PIE root *gere- "to become ripe, grow old" (cognates: Sanskrit jara "old age," jarati "makes frail, causes to age;" Avestan zaurvan "old age;" Ossetic zarond "old man;" Armenian cer "old, old man").
- deontology (n.)
- science of moral duty, 1826, from Greek deont-, comb. form of deon "that which is binding, duty," neuter present participle of dei "is binding;" + -ology. Said to have been coined by Bentham. Related: Deontological.
