Where does “decimator” come from?

decimator (Latin) comes from Latin decimō, from Latin Decimus, from Latin decem, from Latin -nus, from Proto-Italic -nos, from Proto-Indo-European -nós — Creates verbal adjectives from roots.

decimator (Latin): second-person singular future passive imperative...

Definitions

second-person singular future passive imperative...

Ancestry of “decimator”, step by step

Step	Language	Word	Meaning
1	Latin	decimō	to decimate (select every tenth person for punishment)
2	Latin	Decimus	originally used for a tenth-born son
3	Latin	decem	ten; 10
4	Latin	-nus	-an
5	Proto-Italic	-nos	Creates verbal adjectives from verb stems
6	Proto-Indo-European	-nós	Creates verbal adjectives from roots

Every word from Proto-Indo-European -nós →Every word from Latin -nus →Every word from Latin decem →