air line (English, noun)
expansion: air line (plural air lines)
Senses:
glosses: A pipe or tube supplying air or compressed air.
topics: rail-transport
railways
transport
glosses: A railroad following a very flat, straight route between two endpoints in order to minimize travel times, choosing the shortest, most direct route practical even if longer route that was more advantageous was available.
Forms:
form: air lines
tags: plural