Across:
8 For getting away from other half (‘for’ getting away from ‘other half’ = thehal = HEALTH) to a state synonymous with well-being (HEALTH),
9 Taste (APPETITE) similar to 21 down (APPETITE is similar to ‘hunger’),
10 Popular name in Ireland (PAT-) for English (-E) (PATE) spread (PATE),
11 Some cartel (some cartel) goes crazy? (= anagram indicator) (some cartel = LATECOMERS) They’ve missed the boat! (LATECOMERS),
12 The twins (GEMINI), for example (e.g.), taking up (= reverse indicator) (e.g. = GE-) dress (-MINI) (GEMINI),
14 Detective (DI-) is like death warmed up (-SALLOW) (DISALLOW) in bar (bar/ ban = DISALLOW),
15 What one of those familiar with 21 down (hunger) might bring to the table (HEALTHY APPETITE) for 8 across (‘health’ = HEALTH-) and unknown quantity of (-Y) 9 across (‘appetite’ = APPETITE) (HEALTHY APPETITE),
18 Leaving parties (SEND-OFFS) offends (offends) organisation (= anagram indicator) (offends = SEND-OFF-) and some at the top (‘Some’ at the top = -S) (SEND-OFFS),
20 Sets up (= reverse indicator) a (-A) hospital (-H) near Dublin (-D-) on the hill (Dub = BUD-) (BUDDHA) for religious leader (BUDDHA),
22 If Butler is (if Butler is) wrong (= anagram indicator) (if Butler is = FILIBUSTER), use this to delay Bill in the house? (FILIBUSTER),
24 Ocean liner (SAND) going around Sao Tiago Island (going around ‘SAo tiago islaND’ = SAND),
25 Drugs (E+E = -EE-) found on old politician (Progressive Democrat = -P D-) in boat (ship = SH- -IP) (SHEEP DIP) – one would expect beastly type to get clean after being submerged in this (SHEEP DIP),
26 Noel Coward outed Carl (‘Noel Coward’ outed ‘Carl’ = noeowd = WOODEN) as an unemotional actor (WOODEN).
Down:
1 Nuts thrown by debutantes (‘nuts’ thrown by ‘debutantes’ = debate = DEBATE) gets people talking (DEBATE),
2 Sides with Clintonesque (sides with ‘CLintonesqUE’ = CLUE) bit of evidence (CLUE),
3 The issue (CHILD-) with his (his) novel (= anagram indicator) (his = -ISH) (CHILDISH) – it’s juvenile (CHILDISH),
4 Knocks back (= reverse indicator) spirits, albeit (‘spiriTS ALbeit’ = tsal = LAST) at the back of the queue (LAST),
5 Copyright (-C-) in the possession of agents (spies = SPI-ES) (SPICES) for Nigella and Ginger (SPICES),
6 Energised (STIMULATED) by mimic (mimic/imitate = SIMULATE-) taking in first-time (first ‘Time’ = -T-) director (-D) (STIMULATED),
7 Embark on a journey (START OUT) with sailor (-TAR-) consumed by drink (stout = S- T OUT) (START OUT),
13 It’s not wise (ILL-ADVISED) for Bill (-AD-) to follow Dicky from the local (‘dicky’ locally = ILL-) to awful (= anagram indicator) dives (dives = -VISED) (ILL-ADVISED),
14 Sells drugs (DEALS) in Germany (Germany domain = .de = DE-) for gangsters? (Al Capone’s = Als = -ALS) (DEALS),
16 One (I) speech (= homophone indicator) (‘I’ = ‘eye’ = EYE-) at faculty (-SIGHT) (EYESIGHT) provides vision (EYESIGHT),
17 Creep (CRAWL) is after (= position indicator) a stout dealer (PUB) (PUB CRAWL) for a local tour (PUB CRAWL),
19 Freudian slips dismissing Persian (‘Freudian slips’ dismissing ‘Persian’ = fudlis = FLUIDS) with gin and tonic, for instance (FLUIDS),
21 Craving (HUNGER) for Gandhi’s leadership (‘Gandhis’ leadership = -G-) in confusing (= anagram indicator) Nehru (Nehru = HUN-ER) (HUNGER),
23 Some lose patience (some ‘losE PATience’ = epat) going back over (= reverse indicator) (epat = TAPE) recording (TAPE),
24 Who’s (whos) out (= anagram indicator) (whos = SHOW) to demonstrate the truth of something? (SHOW).