1)
What is "Shamah"?
1.
Rashi: It is astonishment (at what the coming verse relates).
2.
Radak: It is astonishment [at the Sha'arurah]. This is like "Shamemu Alecha Rabim" (Yeshayah 52:14).
3.
Radak: Some texts of Targum Yonasan say Teima astonishment, and some say Taima (finished off), like 'Taimei Maya' (Eruvin 88a).
4.
Malbim: It is desolate. This is due to murder and theft.
2)
What is "Sha'arurah"?
1.
Rashi: It is something repulsive to all.
2.
Radak: It is filth (evil), like "ka'Te'enim ha'Sho'arim" (29:17). Malbim - it is due to adultery and idolatry.