right
surely
A four letter word meaning not kosher is: tref
error Fault
The word pine can have that meaning.
What is a nine letter word meaning very tidy
bare
A four letter word for error can be slip.
abstain
surely
A slang word meaning error means-something bad you have done like me saying " mate you have just made a awful error
mistake
Mistake
postulates
novice
The likely word is "easily" (synonyms are simply or freely).
"Xixixixixi" is not a recognized word or term in English. It may be a typing error or a string of characters without any specific meaning.
A typographical error.