To put in one’s oar; to intermeddle, or give an opinion unasked: as, To be sure, you must put in your oar!
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
oaths * obstropulousNathan Bailey's 1721 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes