Related Clues:

• The 'x' or 'y' in 2x + 3y = 15
• Shifting sound keeps artist up
• Not consistent, with no fixed pattern
• Fugitive’s announcement that he’s here to stay?
• Liable to change, inconsistent
• Practicable involving annual return capable of change
• Passing one chap pinning hairstyle with fancy net
• Element in an algebraic equation
• Feasible involving annual return that may change
• Wavering, likely to survive crossing a river
• Something unstable - having central part removed - will work!
• Evil Arab rogue prone to differ?