Synonym: innocuous, nonmalignant. Similar words: tactlessness, harm, charm, harmed, harmful, harmony, harmonize, harmonious. Meaning: ['hɑrmlɪs /hɑːm-] 
adj. 1. not causing or capable of causing harm 2. not injurious to physical or mental health 3. not producing any toxic effects 4. unlikely to harm or disturb anyone 5. not threatening to life or health; not malignant.
adj. 1. not causing or capable of causing harm 2. not injurious to physical or mental health 3. not producing any toxic effects 4. unlikely to harm or disturb anyone 5. not threatening to life or health; not malignant. 271. The majority of E. coli are in fact considered to be harmless.
272. C. is avirulent, harmless material: materials with euramerican "environmentally safe" standards.
More similar words: tactlessness, harm, charm, harmed, harmful, harmony, harmonize, harmonious, disharmony, less, bless, unless, lesson, endless, careless, witless, harness, hopeless, tactless, nonetheless, reckless, flawless, much less, homeless, senseless, guileless, pointless, breathless, changeless, regardless.