What does the cryptic crossword clue "Fatigue as heinous tax rejigged (10)" mean?

The definition is "Fatigue". The wordplay uses an anagram. anagram of HEINOUS + TAX = EXHAUSTION; definition: "Fatigue" The answer is EXHAUSTION.

Fatigue as heinous tax rejigged (10)

Guardian Cryptic #29680 | 11 Across | 2025-04-28 flower