1. (baseball) a special rule (as in baseball) dealing with situations that arise due to the nature of the playing grounds 
2. A basic principle or rule

Derived forms: ground rules

Type of: rule

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• true cedar
• true dwarf
• true fir
• true flycatcher
• true frog
• true fungus
• true glottis
• true guava
• true heath
• true jasmine
• true laurel
• true lobster
• true lover's knot
• true mahogany
• true marmoset
• true north
• true pepper
• true pine
• true puffball
• true rib
• true sago palm
• true sandalwood
• true seal
• true senna