根据下面资料，回答题
"Family" is of course an elastic word. And in different countries it has different meanings. But when British people say that their society is based on family life, they are thinking of "family" in its narrow, pecuharly European sense of mother, father and children living together in their own house as an economic and social unit. Thus, every British marriage indicates the beginning of a new and independent family--hence the tremendous importance of man-iage in British life. For both man and woman, marriage means leaving one´ s parents and starting one´ s own life. The man´ s first duty will then be to his wife, and the wife´ s to her husband. He will be entirely responsible for her finan-cial support, and she for the running of the new home. Their children will be their common responsi-bility and their alone. Neither the wife´ s parents nor the husband´ s, nor their brothers or sisters,aunts or uncles, have any right to interfere with them--they are their own masters.
Readers of novels like Jane Austen´ s Pride and Prejudice will know that in former times, mar-riage among wealthy families were arranged by the girl´ s parents, that is, it was the parents´ duty to find a suitable husband for their daughter, preferably a rich one, and by skillful encouragement to lead him eventually to ask their permission to marry her. Until that time, the girl was protected and maintained in the parents´ home, and the financial relief of getting rid of her could be seen in their giving the newly married pair a sum of money called a dowry (嫁妆). It is very different today.
Most girls of today get a job when they leave school and become financially independent before their marriage. This has had two results. A girl chooses her own husband, and she gets no dowry. Every coin has two sides; independence for girls is no exception. But it may be a good thing for all of the girls, as their social status are much higher and they are no longer the subordinate(部下，下级) of their parents and husbands.
What does the author mean by“Family is of course an elastic word”?