open question, an

open question

An issue or topic that cannot be readily resolved or decided; a question that has a variety of different answers or perspectives. Whether veganism is good for your health is an open question—you'll get a different take depending on whom you ask. How the government should go about dismantling the organization is still something of an open question.
See also: open, question
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

open question

An unresolved issue, one that has not been finally determined. For example, Whether the town should pave all the unpaved roads remains an open question. In the mid-1800s this term acquired a specific meaning in the British Parliament, that is, "an issue on which members may vote independently, without respect to their party affiliation."
See also: open, question
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

an open ˈquestion

(also open to ˈquestion) a matter that cannot be decided easily or that people hold several different views on: Whether private schools give children a better education is open to question.It’s an open question whether meat is bad for you.
See also: open, question
Farlex Partner Idioms Dictionary © Farlex 2017

open question, an

An issue that has not been finally settled or determined. The adjective open has been so used since the early nineteenth century. The term acquired a specific meaning in the British Parliament: on open questions members may vote as they wish, independent of party. David Masson used it figuratively, as it often is today: “The summary decision of what had hitherto been an open question in the Church” (The Life of John Milton, 1859).
See also: open
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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