Sometimes we go through a situation that we want to say something but we are not able to explain it or frame it, we become speechless and this situation leads us to the embarrassing moment in front of someone.So, here are some ways to explain in a single word that YOU' RE SPEECHLESS. 

DUMBSTRUCK - 
The word 'dumbstruck'' is merely a variant of 'dumbfounded''. You're ''temporarily deprived of the power of speech, as it bu surprise or confusion; dumbfounded.''

NONPLUSSED -
The word ''nonplussed'' is a term you don't hear a lot, but it's out there. When nonplussed is used as a noun, this means's ''a state of utter perplexity.''

TONGUE-TIED -
Remember when you met your girlfriend/boyfriend's parents for the first time? Yeah, it's like that. ''Tongue-tied'' means ''Unable to speak'', as from shyness, embarrassment, or surprise. ''If you find yourself tongue-tied, you often end up suffering from a parallel condition known as flop sweat.

FLUMMOXED -
Flummoxed means ''bewildered, confounded, and confused. ''This is often used in a sentence these days. A current usage might be, ''He was really flummoxed when the boss called on him in the meeting. ''Bottom line, you know it when you see it, or worse when you feel it. 

DISCOMBOBULATED -
You've totally fallen apart. The word apparently means '' to confuse or disconcert; upset; frustrate.  Example - ''She became totally discombobulated at the time of giving her presentation.''

Also Read:

Match-fixing in professional tennis, teenager suspended now

Ways to insult someone without using abusive words

12 funny Wikipedia pages that will make you laugh when you'll read