Where does “estivar” come from?

estivar (Spanish) comes from Medieval Latin stivare, from Latin stīpāre, from Latin stīpō, from Proto-Indo-European stīpos, from Proto-Indo-European steip-.

Ancestry of “estivar”, step by step

Step	Language	Word	Meaning
1	Medieval Latin	stivare	—
2	Latin	stīpāre	—
3	Latin	stīpō	to crowd or press together, compress
4	Proto-Indo-European	stīpos	—
5	Proto-Indo-European	steip-	—

Every word from Proto-Indo-European steip- →Every word from Proto-Indo-European stīpos →Every word from Latin stīpō →