A definition that is too broad includes items which should not be included.
: pens, hockey, doctors, and professors
A pen is an instrument designed for writing words.This definition is too broad because it includes pencils and typewriters as well as pens, and it is too narrow because it fails to include pens that are designed for drawing pictures. …
Here are some examples of definitions that are both too broad and too narrow: Hockey is a game played on ice in Canada. A doctor is a person who treats physical ailments. A professor is a teacher who does research.William Hughes and Jonathan Lavery, Critical Thinking (August 31, 2004), pp. 53-4.
: family member
The definition used in the … provision for sick leave is very broad. It reads “Family member means an employee’s spouse, child, parent, or any other individual related by blood or whose close association with the employee is the equivalent of a family relationship.” The “any other individual related by blood” category is potentially very large, depending on how narrowly the term “related” is to be used. Including those “whose close association with the employee is the equivalent of a family relationship” widens the pool even further. At this point, the definition has also become circular, with a “family member” defined as a person with whom the employee’s relationship is “the equivalent of a family relationship.”Richard Reeves, “Let workers decide who counts as ‘family’ for paid sick and family leave” at AEI (February 20, 2018).
: climate change
Without more evidence and a better definition of what is good or bad, it is impossible to decide whether climate change is something to be feared or welcomed, or something to which we should remain indifferent.Jonathan Katz, “Letters to the Editor” at The Atlantic (March, 2011).
: “creationism” versus “intelligent design”
Charles Thaxton told how, as he explored the idea of intelligent causation in the origin of life, he would sometimes use the term “create.” The term has a perfectly neutral dictionary meaning, but he said he became more and more aware that the term was at once too broad and too specific. Search Google Scholar for academic references in biology to “creation,” and one gets more than 50,000 hits, often referring merely to biological processes that bring certain structures into being. To create simply means to cause something to exist.Jonathan Witt, “The Origin of Intelligent Design” (October 30, 2007).
In common usage, hack refers to any unauthorized attempt to use technology for purposes other than those for which it was meant.” Within these parameters the … scandal falls into the category of hacking, but Penenberg counters that this definition is too broad.Rebecca Greenfield, “All Hacks Are Not Created Equal“, The Atlantic (July 25, 2011).
While the term Black has a psychosocial and political significance, in epidemiology and public health, such a broad term is usually unhelpful. The term covers a wide range of ethnic and cultural backgrounds and is potentially offensive and unreliable. It conceals a remarkable heterogeneity of cultures among diverse African populations, and reinforces racial stereotypes.Agyemang, et al, “Negro, Black, Black African, African Caribbean, African American or what?“, Journal of Epidemiology and Community Health, Volume 59, Issue 12 (November 14, 2005).
Identify the term being defined. Identify the conditions in the definition. Find an item which meets the condition but is obviously not an instance of the term.
On definitions as criteria for referencing things
Words are arbitrary symbols. They enable us to speak about objects, events, and situations. As every dictionary user will undoubtedly confirm, the definition of box — “a container for putting things in, especially one with four stiff straight sides” — provides a description of the meaning of the word box. So the meaning of box is the relation between the word form ([boks] or ) on the one hand and what the definition tries to convey on the other hand. But what does the definition try to convey? The definition provides the criteria which, if met, entitle a speaker to use the word box for a certain object, real or imaginary, that he or she wants to talk about.Plag, Braun, Lappe, and Schramm, Introduction to English Linguistics (April 7, 2009), pp. 141-2.