Definition of speed demon
chiefly US, informal
: someone or something that moves or works very fast The new cook is a regular speed demon. This computer is a real speed demon compared with/to my old computer.
Word by Word Definitions
: prosperity in an undertaking : success
: the act or state of moving swiftly : swiftness
: rate of motion: such as
: to prosper in an undertaking
: get along, fare
: to make haste
: an evil spirit
: a source or agent of evil, harm, distress, or ruin
: an attendant (see 2attendant 1) power or spirit : genius
Seen and Heard
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