You can make 170 valid words from the letters in ARACHNIDAN using the Scrabble US/CAN dictionary.
How many points is ARACHNIDAN worth in Scrabble?
ARACHNIDAN is worth 16 points in Scrabble (US/CAN) and 18 points in Words With Friends.
How do I use the Word Unscrambler tool?
Enter any letters into the input box and press Search. The tool will return every valid English word that can be made from those letters using the dictionary you select.