běn
root
Addition of a horizontal line toward the bottom of 木 (tree) to represent the roots of the tree.
Evolution

Bronze script
Mid Western Zhou (~900 BC)
Seal script
Shuowen (~100 AD)
Clerical script
Eastern Han dynasty (25-220 AD)Regular script
ModernDefinitions
běn
root, origin, source; basis; root; stem; origin; source; this; the current; original; inherent; originally; classifier for books, periodicals, files etc
Component uses
Meaning component in 1 character (1 verified)
Sources
季旭昇《說文新證》p.484-485