Find the word definition

Wikipedia
Antoniadi (lunar crater)

Antoniadi is a large lunar impact crater that lies on the southern hemisphere on the far side of the Moon. The crater intrudes into the southeastern rim of the crater Minnaert, a slightly smaller formation that is significantly more eroded. Attached to the eastern rim of Antoniadi is Numerov, another large, ancient crater similar to Minnaert. Due south of Antoniadi is the small crater Brashear.

Antoniadi (Martian crater)

Antoniadi is a crater on Syrtis Major Planum, Mars, located at 21.5° north latitude and 299.2° west longitude. It is 394 km long and was named after Eugène Michael Antoniadi, a Greek astronomer (1870-1944) who spent most of his life in France.

There is evidence that Antoniadi Crater once contained rivers and lakes. The picture below shows an inverted channel in Antoniadi, as seen by HiRISE. Inverted channels formed from accumulated sediments that were cemented by minerals. These channels eroded into the surface, then the whole area was covered over with sediments. When the sediments were later eroded away, the place where the river channel existed remained because the hardened material were resistant to erosion.