What does "cheater" mean?

I've seen some posts referring to lilies as "cheaters." As if the particular variety was not really a lily. What does this mean?

tia
las

I call lilies that I start in pots ahead of schedule or lilies that are in a greenhouse that bloom before their natural cycle in my yard cheater lilies. It gives me bloom a little earlier. So when I post an OT lily, like 'Robina' that is blooming in May at my house I call it a cheater lily, pretty much letting people know that it was greenhouse grown, but still blooming beautifully.