Noun

1. The B-side of a phonograph record.

   Nice tune, what's on the flipside?

2. A necessary consequence or corollary of something; especially one seen as opposite, or as pro versus con.

   Walking to work is definitely healthier – on the flipside, though, it takes twice as long.

3. the occasion when we meet again (e.g. when I return from work, etc.; said on parting); later or tomorrow.

   See you on the flipside!