Patriots' Day means: A civic holiday commemorating the anniversary of the Battles of Lexington and Concord, the first battles of the American Revolutionary War on April 19, 1775. It was previously celebrated on April 19,. There is no real cause for parental concern; it is descriptive vocabulary rather than risky behaviour. If your teen uses it, context will usually make the intent clear. A short, curious question about where they heard it is usually all that is needed to know whether to follow up.