How did Motijheel get its name?

Being a bustling commercial hub of the capital, we often tend to overlook the curious history of Motijheel. For example, did you know that the area’s past goes back to the Mughal era? Once upon a time, that part of Dhaka was referred to as the Mahal of Mirza Mohammad Mukim—so, the premises of said Mughal official.

There was a pond in the compound, and legend has it that for somereason, this gentleman’s daughter used to throw away jewellery into that pond everyday. Due to this, a theory goes that the pond got labelled as Motijheel (Pearl Lake), and in due course, the whole area came to be known by that name. 
Another etymology that somewhat resonates with the aforementioned one is that Motijheel was the name of a canal or rivulet that flowed in or around the area; then, the label was referred to a particular pond, and eventually, an overall locality adopted the name. 
Sources: Banglapedia; ‘Dacca: History and Romance in Place Names’ by Azimusshan Haider