Definition of headways in US English:

headways

adverb

  • Coal Mining. In a direction parallel to that of the main cleavage of the coal (the cleat). Now historical and rare.

adjective

  • Coal Mining. Designating a passage driven in a direction parallel to that of the main cleavage of the coal (the cleat); of or relating to a headway. Formerly frequently in "headways course". Now historical.

Origin

Late 17th century (in an earlier sense). From head + -ways.

Pronunciation

headways

/ˈhɛdweɪz/