A particularly interesting development in the history of Christianity [related to translation] took place with respect to the Greek term monogenés, literally, ‘only, unique, one of kind.’ It was used of Isaac as the son of Abraham [see Gen. 22:2], though Isaac was not the only son of Abraham, for he had a son Ishmael, and with a later wife Keturah, several sons. But Isaac was the only son of a particular kind, that is to say, the unique son of the promise. The term monogenés was translated into Latin as unigenitus, meaning literally ‘only begotten’ [in English — or likewise traditionally in Chinese: “dúshēng 獨 生,” Italian: “unigenito,” Spanish “unigénito,” or German: “eingeboren”] but in Greek the equivalent of ‘only begotten’ would have two n’s and not just one. Nevertheless, the Latin misinterpretation of monogenés has constituted such a long tradition that any attempt to speak of Jesus as the ‘unique son of God’ rather than the ‘only begotten son’ is often announced as a case of blatant heresy. (Source: Nida 1984, p. 114.)
In Waiwai, the Greek that is translated as “only begotten Son” in English in John 3:16 is translated as cewnan tumumururosa okwe, where the “particle okwe indicates dearness, and it must be included in Waiwai for the expression ‘only begotten Son’ to mean anything like what it means to God or to us as Christians.” (Source: Robert Hawkins (in The Bible Translator 1962, pp. 164ff.)
See also complete verse (John 3:16).