Where does “zootherapeutical” come from?

zootherapeutical (English) comes from English therapeutical, from English therapeutic, from New Latin therapeuticus, from Ancient Greek θεραπευτικός, from Ancient Greek θεραπευτής, from Ancient Greek -τής, from Ancient Greek πεῖρα, from Proto-Indo-European per- — passed , crossed.

Ancestry of “zootherapeutical”, step by step

zootherapeutical traces back through two separate lines of ancestry.

via English therapeutical

StepLanguageWordMeaning
1Englishtherapeuticaltherapeutic; Such an agent
2EnglishtherapeuticOf, or relating to therapy; Having a positive...
3New Latintherapeuticuscuring, healing
4Ancient Greekθεραπευτικόςattentive, helpful, obliging, curative
5Ancient GreekθεραπευτήςOne who waits upon another; attendant
6Ancient Greek-τήςAppended to verbs to form agent nouns
7Ancient Greekπεῖραtrial, experiment, attempt
8Proto-Indo-Europeanper-before, in front; first; to go through
9Proto-Indo-Europeanpr̥tóspassed , crossed

via English zoo

StepLanguageWordMeaning
1EnglishzooA park where live animals are exhibited; Any...
2Ancient Greekζῷονanimal, beast; form, image
3Proto-Hellenicďṓyyonanimal, creature, beast
4Proto-Hellenicgʷyōwyon
5Proto-Indo-Europeangʷyeh₃w-y-om
6Proto-Indo-Europeangʷíh₃wetito live, to be alive
7Proto-Indo-Europeangʷih₃wósalive, living
8Proto-Indo-Europeangʷeih₃w-to live
Every word from Proto-Indo-European pr̥tósEvery word from Proto-Indo-European per-Every word from Ancient Greek -τής