D defs.my
Entry 2 senses Webster, 1913

Upside

/ŭpʹsīd'/ · Up·side · IPA /ˈʌpˌsaɪd/
01 n. The upper side; the part that is uppermost.
  1. 1.
    The upper side; the part that is uppermost.
  2. 2.
    the benefits; the positive features; -- said of a situation or event that has both positive (good) and negative (bad) aspects.
    “These that have turned the world upside down are come hither also.” — Acts xvii. 6.
Phrases & compounds
To be upsides with — to be even with.
Upside down — With the upper part undermost; hence, in confusion; in complete disorder; topsy-turvy.