This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

n. (metrology) An SI unit of length equal to 10−12 meters; alternative spelling of picometre.

n. a metric unit of length equal to one trillionth of a meter

"I also will be using the writertopia picometer but I have to wait until I'm back home on my regular computer."

metric linear unit   

pedometer    piezometer    pyrometer   

pm   

impeachent    100-khz    name-to-address    seamanlike    ultrahigh    1-hz    non-binding    back-testing    nine-digit    undiscussed