caput is the Latin word for "head".
By; from.
After=Post in Latin As in: Post Bellum meaning : after war
To be of Latin (Romanic) origin - the ethnic sense, with Latin ancestors; to speak a Latin (Romanic) language, derived from Latin.
I doubt there is a direct translation for jubilant (see paragraph below for why), but you could say "laetissimus" (pronounced light-iss-im-uss), the superlative of "Laetus", which means happy. Being...