Svenska akademiens ordbok:
https://www.saob.se
Collins:
https://www.collinsdictionary.com
Macmillan:
http://www.macmillandictionary.com
OneLook:
https://www.onelook.com
Merriam-Webster:
https://www.merriam-webster.com
Urban Dictionary:
http://www.urbandictionary.com