CQ
CQ (noun) means an abbreviation used by radio operators meaning "calling any station" — a general call inviting any listener to respond. Example: “The amateur radio operator sent out a CQ, hoping someone would answer from another country.”
How to use CQ
Learner’s notesIn plain EnglishRadio shorthand for "is anyone out there listening" — a general call to start a conversation.
Used almost exclusively in amateur and military radio communication.
Fill the gap
Can you complete this real example?
The amateur radio operator sent out a _____, hoping someone would answer from another country.
Etymology
It is borrowed from French CQ.