Deer rider

Hi,

How can "deer-rider" or "elk-rider" be translated in Quenya and Sindarin? Could anyone help?

Not as easy one in Sindarin give me some time to think about it.

Ok for a name Celevrochon ce-LEV-ro-chon or Celevrochben ce-lev-ROCH-ben.

or Arathrochon a-RATH-ro-chon/Arathrochben a-rath-ROCH-ben.

Thanks a lot. Arathrochon sounds nice.