1. Extremely alarming
   - bloodcurdling, hair-raising

See also: alarming

Encyclopedia: Nightmarish

• multiple sclerosis
• multiple star
• multiple voting
• multiple-choice
• multiplex
• multiplex operation
• multiplexer
• multiplicable
• multiplicand
• multiplication
• multiplication sign
• multiplication table
• multiplicative
• multiplicative inverse
• multiplicatively
• multiplicity
• multiplied
• multiplier
• multiplier factor
• multiplier onion
• multiply
• multipolar
• multipotent
• multiprocessing
• multiprocessor