| 1 | Middle English | ostentacioun | — |
| 2 | Middle French | ostentation | — |
| 3 | Latin | ostentatio | exhibition, display, showing off |
| 4 | Latin | ostentō | — |
| 5 | Latin | ostendō | — |
| 6 | Latin | obs- | in front of |
| 7 | Latin | ob- | towards; against |
| 8 | Latin | obolus | obolus |
| 9 | Ancient Greek | ὀβολός | obol, obolus, used at Athens as both a weight and... |
| 10 | Ancient Greek | ὀβελός | a spit, rod; a horizontal line |
| 11 | Ancient Greek | βέλος | missile, arrow, dart; weapon; something quickly... |
| 12 | Proto-Indo-European | gʷélHos | — |
| 13 | Proto-Indo-European | gʷelH- | to throw, reach, pierce; to hit by throwing |