on-the-floor
on-the-rail
onto
oolong
opacification
opacity
opalescence
opalescent
opaque
open
  open-air
open-circuit
open-discharge
open-end
open-ended
opener
open-faced
open-fire
opening
opening-up
open-kettle

    open-air hanging room

    естественная остывочная с подвесными путями