The Collaborative International Dictionary
Lusus naturae \Lu"sus na*tu"r[ae]\n. [L., fr. lusus sport + naturae, gen. of natura nature.] Sport or freak of nature; a deformed or unnatural production.
Wiktionary
n. A freak of nature.
n. 1 (context historical originally English) A supposed capricious act of Nature regarded as the cause and origin of marked phenotypic anomalies in a given organism. 2 (context chiefly in this concrete sense English) An organism exhibiting marked phænotypic deviation from the norm, seeming to be the result of sportive design.
n. (en-irregular plural of: '''''lusus naturæ''''')
WordNet
n. a person or animal that is markedly unusual or deformed [syn: freak, monster, monstrosity]
Usage examples of "lusus naturae".
I was a lusus naturae, she affirmed, as a village schoolmistress: she was sure my previous history, if known, would make a delightful romance.
You are a miracle of nature madam, a lusus naturae, as the Ancients had it.
Charisse regales us with tales of her exploits at Lusus Naturae, a tiny software company that is trying to make computers understand when people talk to them, and her art, which is making pictures that you look at on a computer.
No one even regarded him as a possibility: fratricide has been held as inconceivable, a lusus naturae, since the days of Cain.
Appalled by the secret menace to human life that she had been scared to think of the ease and the safety in which she had been allowed over twenty odd years to carry agonizing death to so many of her kind, and convinced from the inhuman nature of her practices that she was a lusus naturae, her judges, following sentimental Anglo-Saxon example, might have given her asylum and let her live for years at public expense.
After much debate, they concluded unanimously, that I was only RELPLUM SCALCATH, which is interpreted literally LUSUS NATURAE.