What does the cryptic crossword clue "Old birds back from tea in seconds (4)" mean?

The wordplay uses charade, parts. MOA (synonym of "Old birds") + S (last letter of "tea in seconds") [last letter: "back"] The answer is MOAS.

Old birds back from tea in seconds (4)

Guardian Cryptic #29442 | 28 Down | 2024-07-23 flower