The phrase "a classic definition" is correct and usable in written English.
You can use it when referring to a widely accepted or traditional explanation of a term or concept.
Example: "In literature, a classic definition of a hero is someone who demonstrates courage and noble qualities."
Alternatives: "a traditional definition" or "a standard definition".
A classic definition is that of the political theorist Robert Dahl.
This is called leaving out the parts everyone skips, a classic definition of good writing, also a reason composing a shapely life may be easier than living one.
These judgments occur even when there is little immediate evidence that the attackers had direct ties to terrorist groups and when they do not fit a classic definition of terrorists as those who use violence to advance a political agenda.
But this is a production that succeeds because it shows Oedipus not as the gods' puppet but as a man whose suffering is related to his character flaws; which is a classic definition of tragedy.
This is a classic definition of a great photograph that echoes such masters of the craft as Henri Cartier-Bresson, who sought out "the decisive moment" – that amazing instant when life becomes poetry.
If that sounds like a flattering description of Facebook's "groups" (often rallying people with whimsical fads and aversions), then it is worth recalling a classic definition of the modern nation-state.
'A perception without an object' is the classic definition of a hallucination and has been in use since the end of the 19th century (Ey, 1973).
A striking contrast was presented by France, which would not budge from an astringent and classic definition of what comprised the secular: a strict separation of religion from the state, or, for that matter, from the public domain.
This, however, is an artifact of the classic definition of a major complication, which includes transfusions.
They agree that A) it would be the classic definition of insanity were Obama to just again militarily intervene in a centuries long religious (not very) civil war; and B) it was Iran and Maliki who refused to give immunity to remaining American soldiers thereby scuttling a residual American presence there.
The general refusal of The New York Times and its writers and editors to recognize that people who intentionally target and murder civilians, whether on a bus in Gaza or in a hotel in Mumbai, are attempting to alter a political situation (the classic definition of terrorism) and are therefore terrorists defies logic.
