There are a number of questions recently which ask, "What is the domain of this function?" or something similar.
Strictly speaking the domain is part of the definition of any function in the first place. Actually "the" domain is indeterminate from the data given in such questions. The real question being asked tends to be something like, "What is the largest subset of the real numbers on which this formula defines a real-valued function?" (because of course the range often goes undescribed too, and if I add an infinity symbol to the range I can possibly change the domain...).
I guess it is just lazy shorthand, but is it essentially benign? Or are there real problems? Or am I wrong to be irritated?
Most such questions seem to inherit their defects from the source material, rather than being misunderstandings perpetrated by people asking questions.