be off base

1. To be inaccurate or wrong. I never once said that! Your reporter is completely off base in her accusations. I thought I knew what real estate costs were like around here, but, wow—I was totally off base! Wow, it seems the polling data for the gubernatorial election was way off base.

2. baseball Of a runner, to not or no longer be touching the base. The pitcher saw that the runner at first was off base and threw him out. If you're off base like that, you better be cognizant of what is going on at the plate! Watch it out there—this pitcher's got a great move to first. If you're too far off base, you're done.