ὤμοσεν (omosen)
ὤμοσεν is an Ancient Greek form of ὄμνυμι, meaning “swear, take an oath”. It is the 3rd person singular aorist active indicative.
Found 64 times in the Ancient Greek texts on Socratos.
Where it is used
Apollonius Rhodius, Argonautica 2.291: ὧς φαμένη λοιβὴν Στυγὸς ὤμοσεν, ἥ τε θεοῖσιν
New Testament, Hebrews 7.21: ὁ δὲ μετὰ ὁρκωμοσίας διὰ τοῦ λέγοντος πρὸς αἰτόν Ὤμοσεν Κύριος, καὶ οὐ μεταμεληθήσεται, Σὺ ἱερεὺς εἰς τὸν αἰῶνα,)
All forms of ὄμνυμι (conjugation table)
Source: Socratos (socratos.org), a free reader for Ancient Greek and Latin. Grammar from the Perseus Treebank and Morpheus; dictionary entries from Liddell-Scott-Jones, A Greek-English Lexicon (Perseus Digital Library, CC BY-SA). Counts are from the texts on Socratos.