principalprincipal2 adjectiveadj1most importantSYN MAINPortland is one of the principal unloading points for Japanese automobiles.
Gulf’s strategy of concentrating on its principal business of oil and gas production
As principal shareholders in the company, no one has a greater interest in its management.
Baxter Healthcare is the principal subsidiary of Baxter International Inc. (=the largest company owned by them).
Teaching is her primary source of income.
the country’s principal trading partner
2FINANCE relating to the original amount of a loan, rather than any interestThe total principal amount of debentures being sold was increased to $75 million.
A new government may be unwilling to repay interest on the principal sum loaned.