Possible to consider or be considered; conceivable: plans that were not even thinkable. (adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "thinkable" in a sentence
"That the current system is dysfunctional enough that such a thing might soon become thinkable - and for the same reason illegal abortion was once thinkable, that is, because at least some patients were sufficiently desperate to demand the service - is my point."
"This entire trend toward women's secular leadership makes it more "thinkable" that women can become religious leaders as well."
"Okay, while probably "thinkable," but not realistic."