Online Dictionaries:
https://dictionary.cambridge.org/ - Cambridge
https://www.ldoceonline.com/ - Longman
https://dictionary.reference.com/ - Online dictionary
https://slovniky.lingea.sk/Home.aspx?set=ensk&n=7fffff – English – Slovak online dictionary Lingea
https://www.urbandictionary.com/ - Online dictionary of slang words and phrases