ground speed ground sparrow • ground squirrel · · · Info · Definitions · Characters · · ground speed · · Text Common · · Latin · · Scripts 12 · · Length 2 · · Syllables Definitions · · · (noun) the speed of an aircraft relative to the ground. Synonyms: groundspeed. · · Noun Definition 1 Characters · · space U+0020 d latin small letter d U+0064 e latin small letter e U+0065 g latin small letter g U+0067 n latin small letter n U+006E o latin small letter o U+006F p latin small letter p U+0070 r latin small letter r U+0072 s latin small letter s U+0073 u latin small letter u U+0075