Go off on a tangent

Posted by ESC on April 14, 2008 at 10:08:

In Reply to: Go off on a tangent posted by Sharzad on April 14, 2008 at 10:04:

: What does 'go off on a tangent' mean?

Regarding conversation, it means talk off topic. The person is talking about Subject 1 and gets distracted and starts talking about Subject 2. Or if a person is housecleaning, finds a box of old pictures and abandons the original job to research the photos, that's going off on a tangent. Tangent means "diverging from an original purpose or course" (Merriam-Webster).