spelunking

 
Pronunciation: /spɪˈlʌŋkɪŋ/

noun

[mass noun] North American
  • the exploration of caves, especially as a hobby: Neil spoke of the virginal spelunking in the mountains [as modifier]: a spelunking tour at Luray Caverns

Derivatives

spelunker

noun

Origin:

1940s: from obsolete spelunk 'cave' (from Latin spelunca) + -ing1