|helə|flintə noun
( -s )
Etymology: Swedish, from hälle- slab, rock (from Old Swedish hællo-, hælla ) + flinta flint, from Old Swedish; akin to Old Norse hella cliff, mountain, Gothic hallus cliff, and to Old English flint — more at hill , flint
: a very compact banded rock resembling felsite and consisting of minute particles of feldspar and quartz with fine scales of mica and chlorite
• häl·le·flin·toid -ntˌȯid adjective