# Soft Fork

idiom · CEFR C1

Source: https://englishreference.com/idiom/soft-fork
Updated: 2026-07-19

## Meaning

A backward-compatible protocol upgrade that older software still accepts under certain conditions.

## Examples

- SegWit was introduced through a soft fork.
- A soft fork tightens the rules without forcing older nodes off the network.
- Unlike its harder cousin, a soft fork stays backward-compatible, so nodes that never upgrade still accept the new blocks as valid.

## Origin

Soft signals that the change stays compatible with previous versions. (disputed)

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.