How do I solve 16 down in Daily Telegraph Cryptic 31254?

Question

Accepted Answer

16 down reads "Gerry's backing musician showing a bit of heart" (9 letters); the answer is PACEMAKER. It's a double-definition clue: two separate definitions of the same word sit side by side. No wordplay split and no indicators — both halves of the clue define the answer. The full step-by-step breakdown is on this page.

Gerry's backing musician showing a bit of heart (9)

16D — Gerry's backing musician showing a bit of heart (9) — PACEMAKER