 By making an inappropriate analogy with words like bilingual and bilateral containing the Latin prefix " <unk> " ( meaning " two " in Latin ) , the word bikini was first back @-@ derived as consisting of two parts , [ bi + <unk> ] by Rudi Gernreich , who introduced the monokini in 1964 . Later swimsuit designs like the tankini and <unk> further cemented this false assumption . Over time the " – <unk> family " ( as dubbed by author William Safire ) , including the " – ini sisters " ( as dubbed by designer Anne Cole ) , expanded into a variety of swimwear , often with an innovative lexicon , including the monokini ( also <unk> or <unk> ) , <unk> , tankini , <unk> , <unk> ( also <unk> ) , <unk> , and <unk> . The Language Report , compiled by lexicographer Susie Dent and published by the Oxford University Press ( <unk> ) in 2003 , considers lexicographic inventions like bandeaukini and <unk> , two variants of the tankini , important to observe . Although " bikini " was originally a registered trademark of Réard , it has since become genericized . 
