1. Extremely alarming
   - hair-raising, nightmarish

See also: alarming

• regularity
• regularization
• regularize
• regularly
• regulate
• regulated
• regulating
• regulation
• regulation time
• regulative
• regulator
• regulator gene
• regulatory
• regulatory agency
• regulatory authority
• regulatory gene
• regulatory offence
• regulatory offense
• regulo
• Regulus
• Regulus calendula
• Regulus regulus
• Regulus satrata
• regur
• regur soil