Definition: A "lieutenant commander" is a type of officer in the navy. This person has a rank that is higher than a lieutenant but lower than a commander.
In a more advanced context, you might encounter discussions about military hierarchy or strategies, where the role of a lieutenant commander could be emphasized in leadership or operational tasks.
In general usage in English, "lieutenant" can also refer to someone who acts as a deputy or assistant, but in this specific context, it relates only to military ranks.
While "lieutenant commander" does not have specific idioms or phrasal verbs associated with it, the word "lieutenant" can be used in phrases like "second in command," indicating someone who assists or supports a leader.
"Lieutenant commander" is a military term for an officer's rank in the navy, positioned between lieutenant and commander.