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spyhole | |||
hatch; sight hole (Trockner); inspection hole (Trockner); spy hole (Trockner) | |||
sight glass | |||
eye; eye-sight; eyehole | |||
bye hole; observation hole; peep hole; peephole; sight hole | |||
end-door window | |||
entrance door; entry door | |||
tell-tale hole | |||
inspection hole (an Koksöfen) | |||
inspection window; inspection panel; sight opening; display window | |||
inspection hole; peep-hole | |||
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sight hole |