Causing or able to cause harm; hurtful
Harmful to character or morality; corruptive:
Causing or tending to cause harm, especially to a legal case:
Causing damage or harm; injurious.
(Slang) Extremely bad (bad enough to make one ill). Generally used indirectly with to be.
Inclined to annoy or vex with playful tricks; naughty
Causing harm or injury
Designed or tending to disprove or discredit:
Morally injurious; corrupting; unwholesome
The definition of helpful is someone or something that is useful, that provides assistance or aid, or that is prone to providing aid.
Find another word for deleterious. In this page you can discover 22 synonyms, antonyms, idiomatic expressions, and related words for deleterious, like: harmful, hurtful, injurious, pernicious, unhealthy, damaging, prejudicial, ruining, aiding, assisting and bad.