[scrabblehack]

I’ve thought primates.
Protozoa = “first animals” (Greek) - most basic
Primates = “first (animals)” (Latin) - most important

Yes, Primates is an order; Protozoa is a kingdom.

[Verginius Rufus]

Yes, Protozoa and Primates have related meanings...and ultimately go back to the same Indo-European root (*per-), as do English words like first, forth, former, etc. (English and other Germanic languages often have an "f" where Latin and Greek have a "p"--cf. father/pater, five/pente and fish/piscis).

Protozoa combines Greek protos "first" with zoon "animal" or "living being."