Where does “articulito” come from?

articulito (Spanish) comes from Spanish artículo, from Latin articulus, from Latin artus, from Proto-Indo-European h₂értus, from Proto-Indo-European h₂er- — to fit, to fix, to put together.

Ancestry of “articulito”, step by step

Step	Language	Word	Meaning
1	Spanish	artículo	article
2	Latin	articulus	A point connecting various parts of the body;...
3	Latin	artus	narrow, close, fitted, confined, dense; severe,...
4	Proto-Indo-European	h₂értus	that which is fit together; juncture, ordering
5	Proto-Indo-European	h₂er-	to fit, to fix, to put together

Every word from Proto-Indo-European h₂er- →Every word from Proto-Indo-European h₂értus →Every word from Latin artus →