1. Abounding in or bordered by rocky cliffs or scarps
   "the rock-ribbed coast of Maine"
   - rockbound 
2. Tradition-bound and obstinately opinionated
   "rock-ribbed republican"
   - die-hard

See also: inflexible, rough, unsmooth

• bulk mail
• bulk modulus
• bulkhead
• bulkiness
• bulky
• bull
• bull bay
• bull fiddle
• bull market
• bull mastiff
• Bull Moose Party
• bull neck
• bull nettle
• bull pine
• Bull Run
• bull session
• bull shark
• bull snake
• bull thistle
• bull through
• bull tongue
• bull's eye
• bulla
• bullace
• bullace grape