by_chance
1. [ adverb ] in an incidental manner
Synonyms: incidentally accidentally
Examples:

"these magnificent achievements were only incidentally influenced by Oriental models"

Related terms: incidental incidental
2. [ adverb ] (archaic) through chance, "To sleep, perchance to dream.."
Synonyms: perchance
Related terms: archaism
3. [ adverb ] by accident
Synonyms: by_luck haply
Examples:

"betrayed by a word haply overheard"

4. [ adverb ] without advance planning
Synonyms: unexpectedly accidentally circumstantially
Examples:

"they met accidentally"

Related terms: intentionally unexpected accidental unexpected accidental
Similar spelling:   bechance