When you go on and on about how great your mom's cookies are in a cunning attempt to get her to make some cookies, this is an example of a ploy.
Origin of ployfrom uncertain or unknown; perhaps employ (noun)
Origin of ployPerhaps from employ employment (obsolete)
(third-person singular simple present ploys, present participle ploying, simple past and past participle ployed)
Part or all of this entry has been imported from the 1913 edition of Webster's Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.
Probably abbreviated from deploy.