What does "bouldering" mean?

Climbing, without ropes, on large boulders or boulder-sized objects.

What is a synonym for "bouldering"?

Common synonyms include: climbing.

noun, verb

noun, verb ·Rare ·Advanced level

Noun

1
Climbing, without ropes, on large boulders or boulder-sized objects. uncountable

Verb

"I want to join you for bouldering tomorrow."