ˌ ̷ ̷ ̷ ̷ ̷ ̷ˈtā(ˌ)lēz noun plural
Usage: capitalized
Etymology: New Latin, from Equisetum + -ales
: an order of lower tracheophytes (subdivision Sphenopsida) that have the sporangiophores inserted directly on the axis and have existed since the Devonian — see calamariaceae , equisetaceae ; compare archaeocalamites