One of Rashi's 10 major methods is the word meaning method. One word meaning sub-method is the metonomy sub-method. All languages have means by which words obtain new meanings. Some popular word meaning methods, common to all languages, are
• metonomy-naming by something related: e.g. America defeated Iraq really means the American people defeated the Iraqui people.
• Synechdoche-naming a whole by a part: e.g. give me your hand in marriage (But of course the whole person enters the marriage)
• Synechdoche-naming by a good example of a class: e.g. the word honey refers to anything sweet
• naming by Form - e.g. the Pentagon
• naming by Function- e.g. the United Nations
• naming by Feel-e.g. hardship
• naming by exaggeration-e.g. Break-fast, sky-scraper

In todays Parshah we have the following example of Rashi explaining word meaning using literary techniques:
• Gn31-26a states And Laban said to Jacob, What have you done, that you have stolen away unawares to me, and carried away my daughters, as captives taken with the sword? Rashi explains: The underlined phrase sword-captives really means war-captives.

Rashi's explanation is similar to the etymology of the word Bath-room. Not all bathrooms have baths! But a good example (Synechdoche) of a bathroom is a room with a bath as well as toilet facilities. Similarly a good example of war-captives are sword-captives. However the swords are not necessary!

Sermonic points: Some people think they are with it if they interpret the Bible literally and restrictively. As can be seen from the simple examples of bathroom and sword-captives this is not a proper approach. It is intrinsic to language to use approximations and metaphors. A simple word like bathroom proves this. Consequently when the serious student studies the Bible they must blend both literary and analytic techniques. The Talmud also follows this approach.