AA: I'm Avi Arditti with Rosanne Skirble, and this week on WORDMASTER: more of our conversation with Sol Steinmetz, author of the new book "Semantic Antics: How and Why Words Change Meaning."

RS: Take, for example, the evolution of the word girl. Centuries ago, he says, it simply meant a young person, a child of either sex.

SOL STEINMETZ: "The word boy existed long before. But you compared the boy to a 'wench' or to a 'maid.' Those were the two terms used in reference to a child who was a female. Then, gradually, what happened was that wench took on a pejorative meaning, as did maid -- not so much a pejorative meaning, but maid meant somebody who worked for you, somebody who was, you know ... "

AA: "A housekeeper."

SOL STEINMETZ: "A housekeeper, low class, something like that. So then they needed a word for female child, and they used girl. Girl became a female child."

AA: "Instead of it being unisex originally."

SOL STEINMETZ: "Which it was, for many years."

RS: "These words tell a story. I think that's what's so fascinating to me as I look through the book. Do you have any favorite stories about words that have changed and given us a good story?"

SOL STEINMETZ: "Well, take the word worry for example."

RS: "Worry."

SOL STEINMETZ: "Worry. We don't realize that the original meaning of worry was to choke, either to choke on food -- and in German, if you know German, wuergen means to choke; it's the same word, it's a Germanic word. It meant to choke on food or to actually choke an animal, to kill an animal by choking and so forth.

"And because the choking feeling one has, anxiety one has by choking, it gradually went on to transfer to the actual feeling. How I put it, I'm looking in the book right now, and I say: 'Is it a coincidence that you get a strangling sensation in your chest when you're worried about something? Perhaps not.'"

RS: "As we see words that are in your book evolving, what does this say about language in general?"

SOL STEINMETZ: "What it says about language is that you cannot assume that a word as it's used in a sentence is necessarily the only way that it can be used. If you're a writer, you have to understand that context is very important. If you mean to use a word in a certain way, then you have to make sure that that is what it means. That's why any good writer will have a dictionary in front of him."

RS: "Let me ask you a question here. In the beginning of the interview, you said that you came from a multilingual family."

SOL STEINMETZ: "Yes."

RS: "How many languages do you speak?"

SOL STEINMETZ: "I don't keep track. I actually know many languages, but fluently speaking, I speak about five or six."

RS: "So you would be an ideal person to ask what are some techniques that you would recommend to language learners -- our audience, English language learners -- looking at this book, or looking at words in general, how to learn them and how to study?"

SOL STEINMETZ: "Well, I think I suggested it already, that if you're a foreigner learning English, your best friend is a dictionary. Native speakers assume that the way they speak is the way it's supposed to be spoken, the language. A foreigner learning English should be conscious of the fact that no one word is necessarily the only -- has necessarily only one meaning."

AA: "Well, let me ask you one last question here. As language changes, can you imagine a situation where let's say an audience is listening to a speaker, and maybe older members of the audience are understanding certain words differently than younger people in the crowd are understanding those same words to mean, just because the meaning has evolved?"

RS: "Or doesn't it change that quickly?"

SOL STEINMETZ: "Well, it changes gradually, but you're right, it is often generational. I mean, you can see that particularly in the slang of the African-American community, where bad can mean good. 'He's a bad guy.' That can mean 'He's a good guy.' Now, if you don't belong to that community and you listen to it, you say 'What's he talking about?'

"These things happen all the time and people have this certain second sense about who the speaker is and what he's trying to say. So they grasp the idea behind it, but they think to themselves 'Oh, this fellow is misusing the word. That's not what it means, you know?'"

RS: Lexicographer Sol Steinmetz is a former editorial director of Random House Reference, publisher of his new book, "Semantic Antics: "How and Why Words Change Meaning."

AA: And that's WORDMASTER for this week. WIth Rosanne Skirble, I'm Avi Arditti.