Crossword clue: a word which is joined to another so closely as to lose its proper accent, as the pronoun thee in prithee (pray thee).
1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).
Possible answers
Affixed; subjoined; -- said of a word or particle which leans back upon the preceding word so as to become a part of it,