#IOTD : Knuckle down Getting sincere about something; applyin | English time

#IOTD :
Knuckle down
Getting sincere about something; applying oneself seriously to a job.
"I've been knuckling down some courses this semester, thus I fancy some break times."
"The group project was a disaster, but I was able to knuckle down and finish it in time."

Etymology: The term is derived from the game of marbles, it first appears in the mid-1860s in American English. One puts a knuckle to the ground to assume the shooting position in marbles, thus the term knuckle down.

معادل پارسی: جدی شدن، تقلا کردن