Jill Biden isn’t dialed into contemporary slang. The first lady has spoken candidly about her 45-year marriage to Joe Biden in an intimate new interview — but appears oblivious to the obscene meaning of one activity she says she partakes in with the president, 79. Jill, 70, told Harper’s Bazaar Monday that she and her hubby hash out their “occasional” fights via text message, describing the act as “fexting.” But while the Bidens might think the slang term is a cute amalgamation of the words “fighting” and “texting,” Urban Dictionary defines the word as a crude colloquialism that actually means...