cidal

IPA/saɪdl/
IPA/saɪdl/

cidal — suffix

1. Used to form adjectives meaning 'killing a specific type of living thing' or 'ha

1.suffixC1
Definition

Used to form adjectives meaning 'killing a specific type of living thing' or 'having the power or intention to kill that thing'. For example, a substance described as insecticidal kills insects, while a person described as homicidal intends to murder another human being.

Example

Police arrested a man who reportedly made homicidal statements about his landlord during the argument.

homicidal statements — describing intent to kill another person

After losing his job, Tyler began having suicidal thoughts and agreed to see a counsellor.

suicidal thoughts — describing intent toward oneself

Common collocations
  • homicidal intent
  • suicidal thoughts
  • genocidal regime
  • insecticidal spray
  • fungicidal treatment
  • bactericidal agent
Antonyms
  • life-saving

    Describes something that preserves rather than destroys life

  • protective

    Focuses on shielding rather than killing

Grammar Patterns

noun-stem + -cidal → adjective

Usage Note

The -cidal form is an adjective-forming suffix. Its noun counterpart is -cide. For example, a bactericidal spray (adjective) kills germs, while the spray itself is a bactericide (noun). These two forms are frequently confused by English learners.

Common Mistakes

The farmer bought an insecticidal.
The farmer bought an insecticide.
-cidal forms adjectives, not nouns; use -cide for the noun.
This chemical is cidal.
This chemical is bactericidal.
-cidal cannot stand alone; it must attach to a base noun that names what is killed.

Word family

Synonym discussion

Sense: suffix/1

All four adjectives share the -cidal suffix meaning 'killing', but they differ in what is killed and the context of use. Homicidal refers to one person killing another and is used in legal and criminal contexts (a homicidal attacker). Suicidal describes self-directed killing or self-destructive behaviour and belongs to clinical and psychological settings (suicidal ideation). Genocidal refers to the systematic destruction of an entire ethnic, racial, or religious group and is used in political and historical discourse (a genocidal policy). Insecticidal is much narrower and describes substances that kill insects; it belongs to agriculture and pest control (an insecticidal spray). Choosing the wrong compound can sound absurd or offensive — calling a pesticide 'genocidal' is inappropriate exaggeration, while calling a murder 'insecticidal' makes no sense at all.

homicidalsuicidal ↗genocidalinsecticidal

Common collocations

Nouns

Adverbs

Phrases

  • described as + [noun-stem]cidal
  • considered + [noun-stem]cidal

Etymology

LatinFrenchEnglish

The -cidal suffix comes from Latin caedere ('to cut down, to kill'). In Latin, the combining form -cīda meant 'a killer' (as in homicīda 'a murderer'), and -cīdium meant 'the act of killing' (as in homicīdium 'murder'). French adopted these forms as -cide, and English borrowed them, adding the adjectival ending -al to create -cidal in the 16th and 17th centuries. Early appearances include homicidal in the 1500s and suicidal in the 1700s.