Side boob IS in the OED ;)
https://en.oxforddictionaries.com/definition/side_boob
The travel blurb says otherwise.
The English words "I", "We", "Two" and "Three" are some of the oldest and date back thousands of years. Recent additions to the Oxford English Dictionary include the words "Vlogger", "Sideswiping", and "Fatherkin". Sadly "Sideboob" is yet to be accepted into the OED.
This is obviously an urgent bug that seriously limits gameplay :p