Definition of paranoid adjective from the Oxford Advanced Learner's Dictionary

paranoid

adjective
ˈpærənɔɪd
 
; ˈpærənɔɪd
 
 
(also less frequent paranoiac
ˌpærəˈnɔɪɪk
 
; ˌpærəˈnɔɪɪk
 
ˌpærəˈnɔɪæk
 
; ˌpærəˈnɔɪæk
 
)
1 afraid or suspicious of other people and believing that they are trying to harm you, in a way that is not reasonableShe's getting really paranoid about what other people say about her.2 suffering from a mental illness in which you wrongly believe that other people are trying to harm you or that you are very importantparanoid delusionsparanoid schizophreniaa paranoid killerUsage noteUsage note: afraidfrightened scared terrified alarmed paranoidThese words all describe feeling or showing fear.afraid [not before noun] feeling fear; worried that something bad might happen:There's nothing to be afraid of. Aren't you afraid (that) you'll fall?frightened feeling fear; worried that something bad might happen:a frightened child She was frightened that the glass would break.scared (rather informal) feeling fear; worried that something bad might happen:The thieves got scared and ran away.afraid, frightened or scared?Scared is more informal, more common in speech, and often describes small fears. Afraid cannot come before a noun. It can only take the preposition of, not about. If you are afraid/frightened/scared of somebody/something/doing something or afraid/frightened/scared to do something, you think you are in danger of being hurt or suffering in some way. If you are frightened/scared about something/doing something, it is less a fear for your personal safety and more a worry that something unpleasant might happen.terrified very frightened:I was terrified (that) she wouldn't come. She looked at him with wide, terrified eyes.alarmed afraid that something dangerous or unpleasant might happen:She was alarmed at the prospect of travelling alone.paranoid (rather informal) afraid or suspicious of other people and believing that they are trying to harm you, in a way that is not reasonable:You're just being paranoid.afraid/frightened/scared of spiders, etc.frightened/scared/paranoid aboutafraid/frightened/scared/terrified thatafraid/frightened/scared to open the door, etc.Don't be afraid/frightened/scared/alarmed.