Epanorthosis

An epanorthosis is a figure of speech that signifies emphatic word replacement.[1] The example "thousands, no, millions!" is a stock example. More often, however, epanorthosis signifies immediate and emphatic self-correction, and as such often follows a Freudian slip (either accidental or deliberate).

Examples:

Here the words in italics are technically the epanorthoses, although all of the words following the dash may be considered part of the epanorthosis as well. Striking through words is another way of demonstrating the effect.

A modern variant is the use of ^H to fake a backspace.

References