FAULTY LEXICAL ANALOGY

English for Today by Ganiu Abisoye Bamgbose (Dr GAB)

CROWD AND CROWDY: While crowd means a large number of people gathered together in a disorganised or unruly way, crowdy is a soft Scottish cheese made from buttermilk or sour milk. Its meaning is not related to crowd.
LOUD AND LOUSY: While to be loud is to produce or be capable of producing much noise, to be lousy is to be very poor or bad. So, a lousy person does not necessarily speak loud or talk much.
FAMOUS AND INFAMOUS: Both the famous and infamous persons are well known but to be infamous is to be well known for a bad quality or deed.
DIFFERENT AND INDIFFERENT: Indifferent is not the opposite of different. While different means to be unlike something else, indifferent means to be unconcerned or have no particular interest.
FLAMMABLE AND INFLAMMABLE: Despite appearing like antonyms (words that are opposite in meaning), flammable and inflammable both mean to be easily set on fire.
GAB