Sentence:  The author of this dictionary coined the term <WSD>sesquilingual</WSD> in 1975 to describe people who know one language and part of another, a term that probably applies to the majority of Canadians, who know English and a smattering of French, or vice versa. 
Meaning of the word marked with <WSD> tags:  able to communicate fluently in one language, but only to a degree in another