What it means
To sit on the fence is to dodge picking a side when people want a clear answer. You stay perched in the middle, watching how it plays out before you commit. Sometimes it's just being undecided. Other times it's a proper dig at someone for being spineless or playing safe.
Usage examples
"Everyone’s arguing about which pub to book for Friday and Dan’s still sitting on the fence, waiting to see who wins before he texts back."
"Stop sitting on the fence and tell us which option you actually prefer."
"The politician sat on the fence for weeks before finally taking a stance."
"You can't sit on the fence forever, mate. Either back the plan or say you hate it."
"She's been sitting on the fence about moving in for months, keeping one foot in and one foot out."
Where it comes from
It comes from the literal picture of someone perched on a fence instead of getting down on either side. The figurative use is old in English and was well established by the 19th century, especially in political talk, where it mocked people who wouldn't commit and just kept wobbling in the middle.
