• Principal accomplice
• Principal amount
• Principal authoriser
• Principal bassoonist
• Principal binormal
• Principal cellist
• Principal clarinetist
• Principal concern
• Principal dancer
• Principal danseuse
• Principal debitor
• Principal declarant
• Principal devisee
• Principal earner
• Principal eigenvector
• Principal expositor
• Principal fagot
• Principal flautist
• Principal focus
• Principal furnisher