Synonym is mostly defined as "a same-language equivalent" (Adamska-Sałaciak, 2010; Adamska-Sałaciak, 2013) and "does not exceed the limits of a single language" (Gouws, 2013), while for bilingual contexts the term translational equivalent is used.
(Martin, 1960;Klégr, 2004;Hahn et al., 2005;Hayashi, 2012;Haiyan, 2015;Dinu et al., 2015) recognize interlingual synonymy and use either the term foreignlanguage equivalent, cross-lingual synonym, synonymous translation equivalent or bilingual synonym.