Dictionaries of a major language like English are full of obsolete and obsolescent vocabulary, words that are recorded in written repositories but circumscribed by historical periodization and rarely uttered in everyday speech. Knowledge of such vocabulary is subject to inter-generational slippage. Older speakers may have it as part of their education, experience, or passive knowledge. But younger speakers, who have no living access to words and phrases belonging to past manners and morals, typically encounter them only as part of book learning at best, as when exposed to knights-errant in reading Don Quixote.
The gradual but inexorable oblivion of the lexical riches of a language becomes apparent, for instance, when one teaches a class of twenty eighteen-year-olds in a course on Masterpieces of European Literature at an Ivy League university. All are native speakers of contemporary American English, but in discussing the so-called marriage plot in Jane Austen’s Pride and Prejudice, one quickly discovers that words and phrases such as go-between, marriage portion, portionless, chattel, etc. are not even part of the students’ passive word stock (although dowry is) and have to be glossed ad hoc. One could take the view, of course, that it is fortunate for the current generation that the mores of twenty-first-century American mating and marriage rituals dispense with all the baggage that used to be the ineluctable burden of young women (in particular) seeking to make their way in a man’s world. Sic transeunt onera mundi.