We don't have synonyms for making out yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are taking out, faking out and marking out.
(N) :
a term of American origin dating back to at least 1949, and is used to refer to kissing, including extended French kissing or necking (heavy kissing of the neck, and above), or to acts of non-penetrative sex such as heavy petting ("intimate contact, just short of sexual intercourse").
(N) :
Making out refers to various casual sexual behaviors including kissing and petting.
(N) :
a term of American origin dating back to at least 1949, and is used to refer to kissing, including extended French kissing or necking (heavy kissing of the neck, and above), or to acts of non-penetrative sex such as heavy petting ("intimate contact, just short of sexual intercourse").
(N) :
Making out refers to various casual sexual behaviors including kissing and petting.