The word 'tempura' entered English directly from Japanese in the late 16th or early 17th century, coinciding with early Portuguese and Dutch contact with Japan. The Japanese term itself is believed to be a borrowing from Portuguese, specifically from the words 'temporas' (Ember Days, Catholic days of fasting when meat was replaced with fish or vegetables) or 'tempero' (meaning seasoning or condiment). This etymological journey reflects the cultural exchange where a Portuguese religious term was adapted in Japan to name a specific cooking technique, which was then globally disseminated under its Japanese name. The word's history is a direct record of culinary cross-pollination rather than a composition of classical roots.

This is a loanword from Japanese, adopted into English as a single, unanalyzable lexical unit. Its internal structure is not based on English or Indo-European morphemes.