/ ˈdʒɪbərɪʃ; NAmE / noun
[ U ] ( informal ) words that have no meaning or are impossible to understand
SYN nonsense :
You were talking gibberish in your sleep.
••
WORD ORIGIN
early 16th cent.: perhaps from gibber (but recorded earlier) + the suffix -ish (denoting a language as in Spanish , Swedish , etc.).