Rashi on Deuteronomy 28:20/רש"י על דברים כ״ח:כ׳

1המארה means PAUCITY, similar to (Leviticus 13:51) “a fretting leprosy (ממארה)” (a leprosy that frets the flesh, thus attenuating it).

2המהומה — Onkelos renders this by שגוש which means: A TERRIFYING SOUND.