If someone is “off base,” it means they are wrong or are mistaken about something.
Example: The glass jar was broken before I even entered the room, so your assumption of me being responsible is off base; I never touched it.
‘Off Base’ Origin
This phrase possibly originates from baseball. How so? Well, bases are a big part of this sport. For example, after a batter hits the ball, they run to first base, second base, and potentially all the way back to the home plate, which would result in them scoring a ‘run’ for their team.
Additionally, base runners that are standing on a base can “steal” the next one by running to it. They can do this even before the pitch has been thrown, but it is risky because the pitcher can simply throw the ball to the base they are trying to steal, potentially resulting in an ‘out’ for the runner.
So before attempting to steal a base (this is the part where the expression might come from), a runner might position themselves a short distance away from their current base and a little closer towards the plate they want to advance to. When a base runner is positioned like this, well, he is literally off base. Again, this is risky because if he positions too far away from the current plate he’s on, the pitcher can quickly throw to the baseman on that plate, resulting in the runner being ‘out.’
Anyways, this saying goes back to at least the 19th century. For example, the Piqua Miami Helmet newspaper from the year 1880 uses this expression:
“Yet today he is almost peniless. I saw him last night on his semi-weekly spree. As he said ‘the old man was off his base again.’ I have seen him bet $50 on ‘faro’ when so drunk he could not see the cards.”
- Tim was off base when he said that milk had little to no sugar in it.
- You are barking up the wrong tree if you think I am the one who scratched your car.
Note: The origin of many common idioms and phrases are not clear. In these cases, a theory on how it originated might be given. If no theory is listed, there should still be a quote of the expression on the page. These quotations can give you an idea on how old it is. These quotes are typically the oldest known appearance of the phrase in print (that I could find).