harmful Hear it!

harmful Definition

harm·ful (härm′fəl)

adjective

causing or able to cause harm; hurtful

harmful Related Forms

harm′·fully adverb harm′·ful·ness noun

harmful Synonyms

harmful

modif.

injurious, detrimental, hurtful, noxious, evil, mischievous, ruinous, malefic, demolitionary, internecine, adverse, inimical, harassing, sinister, subversive, incendiary, virulent, calamitous, cataclysmic, corroding, toxic, baleful, nocuous, consumptive, painful, wounding, crippling, bad, malicious, malignant, sinful, pernicious, baneful, unwholesome, pestilential, pestiferous, deleterious, annihilative, corrupting, menacing, ill-omened, dire, morbific, devouring, prejudicial, damaging, corrupt, vicious, insidious, treacherous, devastating, catastrophic, disastrous, wild, murderous, undetermining, sapping, destructive, unhealthy, stunting, habit-forming, killing, fatal, mortal, serious, costly, fraught with harm, doing harm, fraught with evil, painful, sore, extirpative, afflicting, distressing, fell, diabolic, brutal, unhealthful, satanic, demoniac, ill, grievous, mortal, lethal, malevolent, mephitic, venomous, cruel, unfortunate, disadvantageous, felonious, aching, pricking, objectionable, fiendish, maleficent, unpropitious, unlucky, malign, sinistrous, noisome, devilish, corrosive; see also dangerous 1, 2. deadly, ominous, poisonous, wicked.

Antonyms pure, healthful*, good.

harmful Usage Examples

Adjective complement with noun phrase

  • contain: Waste treatment plants remove some of the most poisonous wastes from sewage, but most treated sewage still contains material harmful to the ocean.
  • do: Those who want to learn Gung-fu shall respect these principles and never do anything harmful to these Chinese cultural traditions.

Modifies a noun

  • bacterium: Pets can pass on harmful bacteria that may be present in their feces.
  • substance: May have been poisoned or exposed to a harmful substance.
  • ray: They are totally safe, with no emissions, smells, noise, or harmful rays.
  • micro-organism: Many times, skin problems arise because bacteria find an ideal breeding ground which our skin provides when it is covered with harmful micro-organisms.
  • emission: They are also capable of reducing harmful emissions by 90 % .
  • side-effect: So, in effect, it has a double action: both stimulating oxygen use for better health and reducing oxygen's harmful side-effects.

Modifying Another Word

  • potentially: However, the sun's rays also can be potentially harmful.
  • environmentally: CFCs are now being replaced by less environmentally harmful compounds.
  • sexually: Project 19 Provides services for children and young people who display sexually harmful behavior.
  • positively: A reference that was useful yesterday may be useless or positively harmful today.
  • possibly: Based on these character information, a feature that will identify possibly harmful web sites for mobile platforms shall be developed.
  • particularly: Too much sun is particularly harmful to very young children, who should be kept out of direct sunlight.

Used with adjective complement

  • prove: Badgers, like too many children, have a very sweet tooth, which can prove very harmful for them.
  • consider: None of the failures of the standards in 2001 were considered harmful to consumers ' health.
  • become: But when their children reach eight or nine years old, that curiosity can become harmful for both the children and the parents.

Preposition: in

way: Nitrogen dioxide is harmful in two main ways: it can cause breathing problems and it also contributes to the problem of acid rain.

Preposition: for

child: Carbon monoxide fills the rooms which is very harmful for children 's health.

Preposition: by

inhalation: Hazards Iodine is harmful by inhalation and contact with the skin.