principal / principle [ˈprɪnsəpəl]
principal – adj., adv. & n. – adj. – prominent, most important, of greatest value; 2. highest ranking; 3. of an original source; adv. – chiefly, in the main; n. – 1. a person with the highest rank; 2. leader, noble; 3. the one held legally responsible
principle – n. & v. – n. – 1. origin, source; 2. primary element or precept; 3. fundamental truth; 4. an inclusive statement about a given area; 5. honourable characteristic; v. – 1. establish basics; 2. act upon, influence; 3. originate