【Error】 , 【mistake】 , 【blunder】 , 【slip】 , 【lapse】 , 【faux pas】 , 【bull】 , 【howler】 , 【boner】 are comparable when they denote something (as an act, statement, or belief) that involves a departure from what is, or what is generally held to be, true, right, or proper.
【Error】 implies a straying from a proper course and suggests such guilt as may lie in failure to take proper advantage of a guide (as a record or manuscript, a rule or set of rules, or a principle, law, or code); thus, a typographical 【error】 results when a compositor misreads a manuscript; an 【error】 in addition involves some failure to follow the rules for addition; an 【error】 in conduct is an infraction of an accepted code of manners or morals.
【Mistake】 implies misconception, misunderstanding, a wrong but not always blameworthy judgment, or inadvertence; it expresses less severe criticism than 【error】 .
【Blunder】 is harsher than 【mistake】 or 【error】 ; it commonly implies ignorance or stupidity, sometimes blameworthiness.
【Slip】 carries a stronger implication of inadvertence or accident than 【mistake】 and often, in addition, connotes triviality. Often, especially when it implies a transgression against morality, the word is used euphemistically or ironically.
【Lapse】 , though sometimes used interchangeably with 【slip】 , stresses forgetfulness, weakness, or inattention more than accident; thus, one says a 【lapse】 of memory or a 【slip】 of the pen, but not vice versa.
When used in reference to a moral transgression, it carries a weaker implication of triviality than 【slip】 and a stronger one of a fall from grace or from one’s own standards.
【Faux pas】 is most frequently applied to a 【mistake】 in etiquette.
【Bull】 , 【howler】 , and 【boner】 all three are rather informal terms applicable to blunders (and especially to blunders in speech or writing) that typically have an amusing aspect.
A 【bull】 may be a grotesque 【blunder】 in language typically characterized by some risible incongruity or it may be a mere stupid or gauche 【blunder】 .
A 【howler】 is a gross or ludicrous 【error】 based on ignorance or confusion of ideas; the term is used especially of laughable errors in scholastic recitations or examinations.
A 【boner】 may be a grammatical, logical, or factual 【blunder】 in a piece of writing that is usually so extreme as to be funny <a few historical boners … such as dinosaurs surviving until medieval times —Coulton Waugh > or it may be a ridiculous or embarrassing 【slip】 of the kind that results from a sudden 【lapse】 (as of attention or from tact or decorum).