any of several subterranean, edible, ascomycetous fungi of the genus Tuber
an article or thing of very little value.
a literary, musical, or artistic work of a light or trivial character
a candy made of soft chocolate, shaped into a ball and dusted with cocoa
The following seems like a mistake, but just want to confirm. I think he means to say 'give me the time of day'.
"I try not to disclose my age too often," he says. "When I was first starting out a few chefs wouldn't give me the light of day."
This is from a yahoo news story about a young man making money on truffles.
I am familiar with 'give the time of day' and 'see the light of day', but not with 'give the light of day'.
This person obviously conflated the two sayings into one.