Where does “semi-presidential” come from?

semi-presidential (English) comes from English presidential, from English President, from Latin praesideo, from Latin prae-, from Proto-Italic prai-, from Proto-Indo-European preh₂-, from Proto-Indo-European per-, from Proto-Indo-European pr̥tós — passed , crossed.

Ancestry of “semi-presidential”, step by step

semi-presidential traces back through two separate lines of ancestry.

via English presidential

StepLanguageWordMeaning
1EnglishpresidentialPertaining to a president or presidency;...
2EnglishPresidentAn honorific for the head of state of a republic;...
3LatinpraesideoI sit before or in front of; I sit beforehand; I...
4Latinprae-before; in front; in charge
5Proto-Italicprai-pre-, before
6Proto-Indo-Europeanpreh₂-before, in front
7Proto-Indo-Europeanper-before, in front; first; to go through
8Proto-Indo-Europeanpr̥tóspassed , crossed

via English semi

StepLanguageWordMeaning
1EnglishsemiA semi-detached house; A semitrailer; a...
2Englishsemi-half; partial, incomplete; somewhat, rather,...
3Latinsēmi-half
4Proto-Indo-Europeansēmihalf; partially
Every word from Proto-Indo-European pr̥tósEvery word from Proto-Indo-European per-Every word from Proto-Indo-European preh₂-