Dilemma

Dilemma: The word dilemma is commonly used to describe a difficult situation that requires a difficult decision. However, the word dilemma comes from the Greek meaning "double proposition." It simply means that there is a situation in which a choice must be made between two alternatives -- neither of which may be particularly desirable.

Travesty

Travesty: A lot of people use this word interchangeably with "tragedy" or think it's applicable when describing a very unfortunate event. Actually, "travesty" means a mockery or a parody. That's why you often hear of a court case being a "travesty of justice" -- because it makes a mockery of justice and the law.

Literally

Literally: Some folks get very upset when this term is used in place of its antonym, figuratively. However, in a hyperbolic sense, that meaning is justified. Unfortunately, that sense is literally overused.

Notorious

Notorious: This term is occasionally used correctly in a neutral sense but most people tend to think that it has negative connotations. However, the word "notorious" literally (and simply) means “known” and nothing more. However, its dominant connotation is that the individual is recognizable or known for illicit behavior or wrongdoing.

Fortuitous

Fortuitous: This word means “occurring by chance,” but its resemblance to fortune has given it an adopted sense of “lucky.”

For meticulous adherence to the traditional meaning, use fortuitous only in the sense indicated in this sentence: “His arrival at that moment was fortuitous, because her note had not specified the exact time of her departure.” Nothing in the context qualifies his arrival as fortunate; the sentence merely states that he arrived in time without knowing that he would do so.

The informal meaning is expressed here: “His fortuitous arrival at that very moment enabled him to intercept the incriminating letter.” In this sentence, the time of his appearance is identified as a lucky stroke.

Decimate

Decimate: The word suggests an absolute slaughter, and saying you decimated someone is to say you defeated them absolutely and totally.

However, the literal meaning of this word, as all you lovers of Latin know all too well, is “to reduce by one-tenth,” supposedly from the punitive custom of selecting one out of ten captives by lot and killing those so selected as a show of force against enemies. Reducing by 10% isn't really decimating, is it?

PERUSE

Peruse: Some words lose their original meaning while others become so twisted that they end up meaning the opposite what they actually mean.

This victim of definition reversal, peruse, means "to use thoroughly," and its first sense is that of careful steady or attentive reading. However, since so many writers have employed it as a synonym for scan, its second sense is now "to look over or through in a casual or cursory manner."