1. Of or pertaining to, or used for, purification; as, lustral days; lustral water 
2. Of or pertaining to a lustrum

Encyclopedia: Lustral

• interoperable
• interparietal suture
• interpellate
• interpellation
• interpenetrate
• interpenetration
• interpersonal
• interpersonal chemistry
• interphalangeal joint
• interphase
• interphone
• interplanetary
• interplanetary dust
• interplanetary gas
• interplanetary medium
• interplanetary space
• interplay
• interpleader
• Interpol
• interpolate
• interpolation
• interpolator
• interpose
• interposition
• interpret