Principal

It grew and is now built on seven principal hills.

The two principal characteristics of a computer are: It responds to a specific instruction set in a well defined manner and it can execute a prerecorded list of instructions call a program.

As the principal founder of Microsoft, Bill gates is one of the most influential and richest people on the planet.

An apple pie is a pie in which the principal filling ingredient is apple.

Manila has been the principal city of the Philippines for four centuries and is the centre of its industrial development as well as the international port of entry.