what does "a swart oath recommending monogenesis"mean?
O'Donnell asked that an exception be made for President Kennedy, Although the din was atrocious, both he and O'Brien heard, the justice of the peace say, with what they regarded as a distinctly unsympathetic inflection, "It's just another homicide case as far as I'm concerned."

The effect on O'Donnell was instantaneous. He uttered a swart oath recommending monogenesis. Thrusting his head forward until their noses nearly grazed, he said, "We're leaving."

Question

what does "a  swart oath recommending monogenesis"mean?
O'Donnell asked that an exception be made for President Kennedy, Although the din was atrocious, both he and O'Brien heard, the justice of the peace say, with what they regarded as a distinctly unsympathetic inflection, "It's just another homicide case as far as I'm concerned."

The effect on O'Donnell was instantaneous. He uttered a swart oath recommending monogenesis. Thrusting his head forward until their noses nearly grazed, he said, "We're leaving."

Answer

Monogenesis means asexual reproduction. It's a delicate way of saying O'Donnell  said "Go f*** yourself" or something similar..

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