Expressions used in Everyday Spoken English in Social and Professional contexts
A 'hump' is literally a 'bump', can describe the most difficult, boring or dangerous part of a job or activity. Colloquially Wednesday is referred to as 'humpday' as once it has passed you are closer to the weekend. When you 'get over the hump' you succeed in surpassing the most challenging part of something. This is a casual colloquial expression.