A child born to parents who aren't married to one another.(noun)
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Use "lovechild" in a sentence
"Cass Cromwell aka Tom Starling, aka the lovechild of Russell Tovey and Danny Dyer finally got to reveal his dark secret."
"Think of it like Blueprint and Tripoli had a lovechild, which is BT."
"Skippy Dies by Paul Murray (Hamish Hamilton) and Slut Lullabies by Gina Frangello (Emergency Press), described as the lovechild of Mary Gaitskill and Philip"