placodontEtymologyFrom placo- + -odont, after scientific Latin Placodus (genus name).placodont means An extinct marine reptile of the order Placodontia. Lexicurio rates it Sui generis — a strength score of 87 out of 100.nounAn extinct marine reptile of the order Placodontia.“The dentition of placodonts was very interesting, as they all had large crushing teeth on the palate.”