Def. 1 (verb) To attempt the same challenging action after failure. Apparently derived from an old adage: "You have to get back on the horse that threw you."

Def. 2 (verb) To get back into a habit. Traditionally this would refer to a good habit, but sarcastically might refer to a bad habit or addiction. Possible confusion with the phrase "on the sauce".
Def. 1 - I know you burned the turkey trying to cook Thanksgiving dinner, but you can't let that stop you if you really want to become a chef. You'll just have to get back on the horse and try cooking it again.

Def. 2 - I'd been trying to do 30 minutes of exercise every day, but my work schedule eventually got so busy I could never make it to the gym. Things have calmed down quite a bit recently though and I keep meaning to get back on the horse and go work out again.
by Peter K. November 28, 2007
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