speechless (adj.)

• aphasic
• aphonic
• breathless
• brief
• brusque
• close
• closemouthed
• concise
• curt
• dazed
• dumb
• dumbfounded
• dumbstricken
• dumbstruck
• inarticulate
• laconic
• mum
• mute
• nonplussed
• quiet
• reserved
• shocked
• short
• silent
• snug
• taciturn
• terse
• thunderstruck
• tongue-tied
• tongueless
• uncommunicative
• untalkative
• voiceless
• wordless