Definition of "sidetrack" [side•track]

• To divert from a main issue or course: I was sidetracked from my work by an unexpected visitor. (verb-transitive)
• To delay or block the progress of deliberately: "a bill that would sidetrack food irradiation in this country” ( Alexis Beck). (verb-transitive)
• To switch from a main railroad track to a siding. (verb-transitive)
• To deviate from a main issue or course. (verb-intransitive)
• To run into a siding. (verb-intransitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "It is kind of a sidetrack from the usual Cabinet fare, but might prove interesting to many of you."
• "It was a great "sidetrack" - they learned more in a week and a half of blogging than I could have taught in a month."
• "It's a sidetrack of an existing well, and the sidetrack is a short sidetrack just to get around the completion."