1. by chance - Adverb
2. by chance - Phrase
without advance planning
by accident
through chance
Source: WordNetNo man was ever wise by chance. Seneca
Children weren't born by chance and we are held responsible for their salvation. John Chrysostom
No one crosses our path by chance. And we don't enter someone's life without a reason. Source: Internet
A fool by chance may say a wise thing. Dutch Proverb
Some small spark may yet by chance lie hidden. Latin Proverb
By chance a cripple may catch a hare. Scottish Proverb