trackball -- (an electronic device consisting of a rotatable ball in a housing; used to position the cursor and move images on a computer screen; "a trackball is essentially an upside-down mouse")
dictionary, definition of, free online dictionary, online dictionary, English dictionary, dict, diction, dictonary, glossary, define, definitions, meaning, word of the day, spelling, pronunciation, dictio, dictiona, dic, dicti, dictionar
(TTS Sound)