Where does “संध्याकाल” come from?

संध्याकाल (Sanskrit) comes from Sanskrit संध्या, from Sanskrit संधि, from Sanskrit संधा, from Sanskrit सम्, from Sanskrit आस, from Proto-Indo-European sewh₁- — to press, push.

Ancestry of “संध्याकाल”, step by step

संध्याकाल traces back through two separate lines of ancestry.

via Sanskrit संध्या

Step	Language	Word	Meaning
1	Sanskrit	संध्या	the act of holding together; a union, junction
2	Sanskrit	संधि	containing a conjunction or transition from one...
3	Sanskrit	संधा	to join, bring together, unite, combine, put together, compound, mix
4	Sanskrit	सम्	to be agitated or disturbed
5	Sanskrit	आस	to have been
6	Proto-Indo-European	sewh₁-	to press, push

via Sanskrit काल

Step	Language	Word	Meaning
1	Sanskrit	काल	black, dark blue; black, dark blue colour; pupil
2	Proto-Turkic	kār	snow
3	Proto-Iranian	karah	fold, of time (during which an action or event happens)

Every word from Proto-Indo-European sewh₁- →Every word from Sanskrit आस →Every word from Sanskrit सम् →