Definition of periscope in US English:



  • An apparatus consisting of a tube attached to a set of mirrors or prisms, by which an observer (typically in a submerged submarine or behind a high obstacle) can see things that are otherwise out of sight.

    • ‘The cork floated on the surface, its quill upright like the periscope of a submarine.’
    • ‘Although cramped and uncomfortable, these boats were fine examples of engineering, with most of the features to be found on normal-sized boats, including a periscope.’
    • ‘The commander has seven optical periscopes which provide 360° observation and a dedicated sight for weapon aiming.’
    • ‘Since mines don't emit sounds, produce heat, make transient sounds or poke periscopes through the surface of the water to attack their prey, minemen have to look for shapes.’
    • ‘The retractable masts viewed from bow to stern are the periscopes, radar antennae, radio and satellite communications and navigation masts.’
    • ‘There was the conning tower with the periscope easily identifiable inside; there were the access hatches.’
    • ‘The driver's compartment is equipped with three observation periscopes.’
    • ‘One idea that remained on paper only was to train seagulls to land on periscopes at sea thus giving away the position of a submarine!’
    • ‘Another classic application of the field lens is in a periscope or endoscope.’
    • ‘To see above and below the water, mudskippers pop their movable eyes out of the water and move them up and down like a submarine periscope.’
    • ‘When disturbed, they dive headfirst under water, or they sink slowly into the water until only their heads are above water, like submarine periscopes.’
    • ‘Closer examination revealed a pair of compound eyes mounted on movable stalks, protruding from a burrow and rotating independently, like the periscopes of a submarine.’
    • ‘Human lookouts are used to detect submarine periscopes.’
    • ‘As you descend, your first sight of the submarine will be a selection of masts and periscopes rising from the conning tower.’
    • ‘Their compound eyes look like a periscope of a submarine and allow the lobster to see images in a mosaic pattern.’
    • ‘Primitive periscopes, made from long wooden boxes with mirrors, were arranged so that an observer could look over the rim of the trench without getting hit by a sniper's bullet.’
    • ‘The driver is equipped with three forward periscopes plus one periscope to the left.’
    • ‘The gunner's station is equipped with gunner's main sight, three periscopes and a visual display unit.’
    • ‘Visitors can try out a submariner's bunk, learn how to control the boat as it dives, look through the periscope, detect underwater sounds on a hydrophone, climb into a mock conning tower and operate an escape chamber.’
    • ‘He also made the submarine commander glare through the periscope with his right eye so that it could be seen more easily.’