undeleterious

adjective

1. injurious to health: deleterious gases.
2. harmful; injurious: deleterious influences.

adjective

1. harmful; injurious; hurtful

adj.1640s, from Medieval Latin deleterius, from Greek deleterios “noxious,” from deleter “destroyer,” from deleisthai “to hurt, injure.” Related: Deleteriously; deleteriousness. adj.

1. Having a harmful effect; injurious.