1. (

• Carboniferous ,
• Carboniferous_period

) from 345 million to 280 million years ago ;

1. (

• carboniferous ,

) of or relating to the Carboniferous geologic era; "carboniferous rock system" ;

2. (

• carbonaceous ,
• carbonous ,
• carbonic ,
• carboniferous

) relating to or consisting of or yielding carbon ;