How do I solve 14 down in Daily Telegraph Cryptic 31236?

Question

Accepted Answer

14 down reads "One mammal thanks another group in combat" (9 letters); the answer is BATTALION. It's a charade: the answer breaks into parts in clue order, each part clued by a word or short phrase. No indicators needed; watch for standard abbreviations (RA = artist, US = American, IN = at home) and short synonyms. The full step-by-step breakdown is on this page.

One mammal thanks another group in combat (9)

14D — One mammal thanks another group in combat (9) — BATTALION