They are synonyms, because they are different words for the same thing.
Two synonyms for the word "entrails" are "guts" and "innards." Both terms refer to the internal organs, particularly those found in the abdominal cavity of animals.
guts or intestines
entrails
Entrails are essentially the guts of a person, animal, etc. Therefore, fish entrails would be, by definition, the fish's insides.
They can be antonyms (opposite meanings), not synonyms.
go on www.synonym.com 4 synonyms & antonyms
there is no synonyms or antonyms for convection current
Antonyms: opposite. Synonyms: similar.
Synonyms: moving Antonyms: Fixed, Stationary
they are closer to synonyms than antonyms, although they are not direct synonyms.
Synonyms. Synonyms are words the same in meaning and antonyms are opposites
They are synonyms. Synonyms have similar meanings, antonyms have opposing meanings.