The term AS FIT AS A FIDDLE is a SIMILE, which is a figure of speech that compares two things using the words 'LIKE' or 'AS'. The crossword solutions for this term are SIMILE (6 letters) and STRAD (5 letters). The phrase 'AS FIT AS a FIDDLE' is an idiom that means to be in good health or condition. It is believed to have originated in the 16th century, when the violin was first invented. The phrase is still used today to describe someone who is healthy and strong.