Answer: toiled

AnswerCrossword Clue
TOILEDDug ditches, e.g.
toiledTOIL, to work hard
toiledhard, exhausting work
toiledto work hard
TOILEDPut in work
TOILEDPut one's nose to the grindstone
TOILEDSlogged away
TOILEDApplied elbow grease
TOILEDWorked a 12-hour shift, e.g.
TOILEDWorked really, really hard
TOILEDWorked like a dog
TOILEDSlaved
TOILEDBroke one's back
TOILEDLabored
TOILEDWorked like a Trojan.
TOILEDWorked hard
TOILEDWorked really hard
TOILEDKept one's nose to the grindstone
TOILEDPlugged away
TOILEDWorked one's fingers to the bone
TOILEDWorked
TOILEDWorked arduously
TOILEDSlaved away