Multiple choice general knowledge

What do the following words have in common??? {millionaire, fish, toothbrush, fruit, and synonym}

  1. None of them have synonyms

  2. These words are adapted to English from other languages

  3. They are all used only as nouns

  4. None of these

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is a linguistic riddle. Each listed word (millionaire, fish, toothbrush, fruit, synonym) is interesting because it describes itself - 'millionaire' has no synonym meaning 'person with a million', 'fish' has no true synonym (no single-word replacement), 'toothbrush' is irreplaceable, 'fruit' is a unique category, and 'synonym' ironically has no synonym. The commonality is that none have perfect synonyms.