Pronunciation: [ɹˈʌʃ ˈɒf] (IPA) 
The phrase "rush off" is spelled /rʌʃ ɒf/ in IPA phonetic transcription. The first part of the word, "rush," is pronounced with the short u sound /ʌ/ followed by the voiceless alveolar fricative /ʃ/. The second part of the phrase, "off," is pronounced with the short o sound /ɒ/ followed by the voiceless labiodental fricative /f/. The phrase means to depart quickly or abruptly from a place or situation.
The term "rush off" can be defined as an action of hurrying or moving quickly away from a particular location or situation. It usually implies a sense of urgency or haste in one's departure. The phrase is often used to describe when someone abruptly leaves in a hurry, without spending much time or giving full attention to their current environment or the people around them.
"Rush off" is commonly associated with situations where individuals need to leave quickly due to time constraints, emergency situations, or an urgent need to attend to something else. It may involve abruptly ending a conversation, leaving a gathering or event, or swiftly departing from a place of work or study.
This phrase can also connote a sense of impatience or preoccupation, where the person in question may not appear fully engaged in their current activities. For example, they might be easily distracted or disinterested, making them eager to leave as soon as possible.
Overall, "rush off" can be understood as the act of swiftly departing while conveying a sense of urgency, regardless of the reasons behind it.
The word "rush" has its origins in the Old English word "riscian" which means "to make a sudden movement". Over time, it evolved into various Middle English forms such as "ruschen" and "risshe". The term "off" originates from Old English "of" which means "away" or "from".
The phrase "rush off" combines the word "rush" with the preposition "off". It essentially conveys the idea of quickly departing, leaving, or going away in a hurried manner. The etymology of "rush off" is the combination of these two individual words and their respective linguistic backgrounds.
