indefinable /in-di-fīˈnə-bl/

1. That cannot be defined
2. Hard to identify or describe

• curtain walling
• curtain walls
• curtal
• curtalax
• curtalaxe
• curtalaxes
• curtal friar
• curtal friars
• curtals
• curtana
• curtanas
• curtate
• curtate annuity
• curtation
• curtations
• curtaxe
• curtaxes
• curter
• curtesies
• curtest
• curtesy
• curtilage
• curtilages
• curtly
• curtness