Merriam Webster’s Dictionary defines a wink as to:
close and open one eye quickly, typically to indicate that something is a joke or a secret or as a signal of affection or greeting.
In the light of this definition, we can surmise that the whole ‘frosty’ thing when Trump and Putin met was a high-powered act to throw the liberal mainstream media off their backs.
Why did Putin not respond to Trump’s wink? So as not to send false messages to the international press. Imagine the headlines if Putin winked back.
Or it may be it was a silent chastisment to Trump who thought the cameras won’t catch the wink, which was him (Trump) telling Putin, “We fooled the liberal mainstream media, haven’t we? So as soon as they’re out of the room we’ll have a good laugh about it.”