(In negative contexts) a single word, any word at all.
Origin
Early 20th century; earliest use found in Crucifixion. Now chiefly after the use in the spiritual ‘Crucifixion’ (also called ‘He never said a Mumbling Word’): see quot. 1913.
Definition of mumbling word in US English:
mumbling word
noun
US
(In negative contexts) a single word, any word at all.
Origin
Early 20th century; earliest use found in Crucifixion. Now chiefly after the use in the spiritual ‘Crucifixion’ (also called ‘He never said a Mumbling Word’): see quot. 1913.