definition of
principal

[1] #1 principal s. [chief, main, primary, master] most important element; "the chief aim of living"; "the main doors were of solid glass"; "the principal rivers of America"; "the principal example"; "policemen were primary targets"; "the master bedroom"; "a master switch". wn

[2] #2 principal n. the original amount of a debt on which interest is calculated. wn

[3] #3 principal n. [school principal, head teacher, head] the educator who has executive authority for a school; "she sent unruly pupils to see the principal". wn

[4] #4 principal n. [star, lead] an actor who plays a principal role. wn

[5] #5 principal n. [corpus, principal sum] capital as contrasted with the income derived from it. wn