Is the Salah (prayer) named after one of the bones at the end of the spinal column, and what is the reason for this naming?

Perhaps the word salat (prayer) is derived from al-salawayn, which are two veins in the buttocks that bend during bowing (rukūʿ) and prostration (sujūd). In the linguistic sense, salat means supplication (duʿāʾ) and seeking forgiveness (istighfār). From this, the name salat, referring to the ritual prayer with bowing and prostration, was derived, because it encompasses supplication and seeking forgiveness. It has also been said that it is taken from "I straightened the stick" (ṣallaytu al-ʿūd), because prayer guides its performer to uprightness. It has also been said that it is a connection between the servant and his Creator, bringing him closer to His mercy, pleasure, and Paradise.