Definitions
an optical instrument that provides a view of an otherwise obstructed field
Word origin
Formed in English from peri- + -scope.
Used in a sentence
“[…] will show it not only enlarging the periscope of knowledge, but contributing to the amelioration of the condition of unfortunate and suffering humanity […]”
“Thousands of ungainly black-beaked heads would periscope and freeze in the direction of the approaching intruder.”
“Areas of barren sand are likely spots to look for its [the turtle's] periscoping head. Its fondness for the bottom is equally matched by its ability to quickly disappear and tunnel into it.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer2 curated clues
01“Submarine viewer”9 letters
02“Submarine viewing tube”9 letters
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