inarticulate
1 blurred, incoherent, incomprehensible, indistinct, muffled, mumbled, unclear, unintelligible
2 dumb, mute, silent, speechless, tongue-tied, unspoken, unuttered, unvoiced, voiceless, wordless
3 faltering, halting, hesitant, poorly spoken
Antonyms
1 & 3 articulate, clear, coherent, comprehensible, intelligible, well-spoken