We don't have synonyms for dry hump yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are dry up, dry sump and dry cup.
(v) :
Alternative spelling of dry-hump. [(ambitransitive, slang) To simulate sexual intercourse without the genitalia directly touching, i.e. while wearing clothes, or by rubbing the genitals against something else.]
(v) :
Alternative spelling of dry-hump. [(ambitransitive, slang) To simulate sexual intercourse without the genitalia directly touching, i.e. while wearing clothes, or by rubbing the genitals against something else.]