lodestar (n.)

• ambition
• aspiration
• basis
• calling
• cause
• comet
• consideration
• cynosure
• daystar
• focus
• goal
• ground
• ideal
• inspiration
• intention
• lodestone
• magnet
• magnetite
• mainspring
• matter
• motive
• orb
• paramagnet
• polestar
• principle
• reason
• sake
• score
• solenoid
• source
• sphere
• spring
• stars
• vocation