temporarily deprived of speech by strong emotion, physical weakness, exhaustion, etc.: speechless with alarm.
characterized by absence or loss of speech: speechless joy.
lacking the faculty of speech; dumb.
not expressed in speech or words: speechless compliments.
refraining from speech.
Origin: before 1000; Middle English specheles, Old English spǣclēas. Related forms
1. dumfounded, shocked, mute. 3. silent, mute.
1–3. loquacious, voluble, talkative.