An obstruction.
"When we got to the bar, he ordered a stonewall as his first round."
Alternative letter-case form of stonewall (“alcoholic drink”)
obstruct or hinder any discussion
"Nixon stonewalled the Watergate investigation"
"When she doesn't like to face a problem, she simply stonewalls"
engage in delaying tactics or refuse to cooperate
"The President stonewalled when he realized the plot was being uncovered by a journalist"
To obstruct.
"The lawyer tried to stonewall the investigation by refusing to answer any direct questions about the client's whereabouts."
Certain, definite.
"The witness gave a stonewall answer when asked if he had seen the defendant that night."
A series of riots in 1969 New York City, beginning with the patrons of the gay bar "The Stonewall Inn" resisting police arrest, which marked the beginning of the militant gay rights movement.
"Many historians trace the modern militant gay rights movement back to the historic stonewall riots that erupted at The Stonewall Inn in 1969 when patrons refused to be arrested by police."