to continue doing something, even when it is difficult.

I will stay the course and finish the job I was hired to do.

Etymology: based on the literal meaning of a ship continuing in the same direction, even in bad conditions

• head and shoulders above [the others/the rest etc.]
• head and shoulders above the rest
• bad-mouth
• bad-mouth someone
• bad-mouth something
• bad workman blames his tools.
• bag and baggage
• bag lady
• bag of bones
• bag of tricks
• bail out
• bail out of
• bail out of something
• bail someone out
• baker's dozen
• balancing act
• ball and chain
• ball-breaker
• ball is in court
• ball is in someone's court
• ball is in your court
• balloon goes up
• ballpark estimate
• ballpark figure
• balls-up