Japanese edit

For pronunciation and definitions of かいこん – see the following entries.
悔恨
[noun] remorse, repent
[verb] to show remorse; to repent; to deeply regret
開梱
[noun] unpacking
[verb] to unpack (to remove from a package)
開墾
[noun] cultivating new land; clearing; reclamation
[verb] to cultivate; to prepare soil for planting
塊根
[noun] (botany) tuberous root​
(This term, かいこん, is the hiragana spelling of the above terms.)