Great fun from Goliath.
A smooth solve, excellently constructed, and loads of fun. Many thanks to Goliath.
A missing J means we don’t have a pangram, but so very close.

ACROSS
1. Slice from the top of sensory organ (6)
SLIVER
S[ensory] (top of) + LIVER (organ)
4. Drunk and beaten (8)
HAMMERED
9. A subject that’s sensitive (6)
ATOPIC
10. Peak of salt intake by Scots? (8)
PINNACLE
NACL (salt) intake by PINE (Scots?)
Scots being one example of a PINE; NaCl the chemical symbol for regular table salt
12. Most indigenous people from the East travel (4)
ROAM
MAOR[i]< (indigenous people, most, <from the East)
13. Lighter feel by the FT? (10)
TOUCHPAPER
TOUCH (feel) by PAPER (the FT? as an example of a paper)
15. Old European king in jeopardy said capital starts to value another king (12)
CZECHOSLOVAK
“CHECK” (king in jeopardy, “said” from chess) + OSLO (capital) + V[alue] A[nother] K[ing} (starts to)
18. OK then, no chav can be a playwright (5,7)
ANTON CHEKHOV
(OK THEN NO CHAV)* (*can be)
21. What might give heart tremor (10)
EARTHQUAKE
Cryptic definition: reverse anagram
EARTH* (*quake) gives HEART
22. Hire car turned over, wrapped around tree (4)
ACER
[hi]RE CA[r]< (<turned over, wrapped around)
24. Owner’s genes in amusing reversal (8)
LANDLORD
(DNA (genes) in DROLL (amusing))< (<reversal)
25. Birch (or not) small and indoors, primarily (6)
BONSAI
B[irch] O[r] N[ot] S[mall] A[nd] I[ndoors] (primarily) – &lit
26. Mistake by expert that’s slipping downwards (8)
PROLAPSE
LAPSE (mistake) by PRO (expert)
27. Woman held by criminal having weapon (6)
CANNON
ANN (woman) held by CON (criminal)
DOWN
1. The Blarney Stone not really a symbol of Ireland (8)
SHAMROCK
SHAM ROCK (The Blarney Stone, not really)
2. Worshipper and procrastinator’s motto (8)
IDOLATER
I DO LATER (procrastinator’s motto)
3. Way out is to be partly flexitarian (4)
EXIT
5. Each cafe or kiosk initially needs a make-over — it’s easy (1,5,2,4)
A PIECE OF CAKE
A PIECE (each) + (CAFE O[r] K[iosk] (initially))* (*needs a make-over)
6. Someone endlessly playing round design for aircraft (10)
MONOPLANES
SOMEON[e]* (endlessly, *playing) round PLAN (design)
7. Instructions to adjust price finally in force (6)
RECIPE
PRICE* (*to adjust) + [forc]E (finally in)
8. Sad bum in dirty clothing (6)
DREARY
REAR (bum) in D[irt]Y (clothing)
11. Do ‘hero versus rogue’ for starters (4,8)
HORS D’OEUVRES
(DO HERO VERSUS)* (*rogue)
14. Fur is cool in China (10)
CHINCHILLA
16. Enters hotel to control wrongdoing (6,2)
CHECKS IN
CHECK (to control) + SIN (wrongdoing)
17. Having core reason to generate hatred (8)
AVERSION
([ha]VI[ng] (core) + REASON)* (*to generate)
19. On the rebound, mate, married, with a double chin (6)
DEWLAP
(PAL (mate) + WED (married))< (<on the rebound)
20. Smile and leave foreigner in Mexico (6)
GRINGO
GRIN (smile) + GO (leave)
23. Heartless, showing lack of awareness (4)
COMA
It is nice the setter is a doctor, but he seems to have forgotten many of the solvers are not.
Ticked LANDLORD, and IDOLATER. I loved SHAMROCK. COMA was clever, a bit too clever. I thought EARTHQUAKE brilliant once I got it.
But, including the medical NHOs, I had lots of quibbles with this crossword. I will not bore you with them all, but I note woman = ANN and indigenous people = MOAR(I) are just silly given how many women’s names and how many types of indigenous people exist in this world.
Thanks Goliath and Oriel
Well, I’m no doctor but I recognised LIVER as an organ, I’ve heard of a PROLAPSE and also of a COMA. Which only leaves ATOPIC as a potentially tricky term but I managed to work out what ‘a subject’ was doing. So I’m not convinced that this puzzle was medically impenetrable. I’d agree with the general criticism of ‘woman’ for a random name but ‘indigenous’ people for MAORI doesn’t feel particularly obscure. So, fewer complaints from this solver. I thought COM(m)MA was a lovely bit of misdirection, share Martyn’s likes for EARTHQUAKE, SHAMROCK, IDOLATER and LANDLORD and I’d throw in TOUCHPAPER for good measure. My only real raised eyebrow was ‘Scots’ = PINE. As a precise pal of mine would say, a Scots Pine is a pine, a Scots is not.
Thanks Goliath and Oriel
I too was rather puzzled by Martyn’s first sentence. If anything, I thought there were perhaps fewer than usual obscure medical references from Goliath – but then I did have a PROLAPSE years ago and am a lifelong sufferer from ATOPIC eczema.
I especially enjoyed EARTHQUAKE, LANDLORD, A PIECE OF CAKE, HORS DOEUVRES, DEWLAP and COMA.
Good to see SLIVER – so many people seem to say ‘slither’ instead.
Thanks to Goliath for the fun and to Oriel for a fine blog.
… but a “Scots ?” could be one, couldn’t it?
Like others here, I loved SHAMROCK, IDOLATER and BONSAI. Nothing to scare the horses here but the fun setting I’ve come to expect from Goliath.
Sadly, 14d is all too true.
Thanks to our ‘doctor in the house’ and Oriel.
I didn’t know the medical meaning of ATOPIC, but it wasn’t hard to get (unlike CZECHOSLOVAK which defeated me with all crossers present). Knowing that the setter is a scientist helped me to spot the pinNACLe, though I agree with the Scots quibble.
However, lots to smile at in this: the SHAM ROCK and I DO LATER (I thought it was spelt IDOLATOR, but you live and learn), the surfaces of DREARY and BONSAI and the sneaky heartless CO(m)MA in particular.
When I first looked at this crossword I thought it impenetrable but then things started falling into place in a way that was great fun. I loved 23down (Coma). Thanks to be Goliath and Oriel
Lots of fun: I didn’t quite finish – the SE quarter had me beat but I enjoyed this – especially Anton Chekhov and Piece of Cake.
Thanks to Goliath and Oriel.
Thanks Goliath and Oriel. I liked the way that 23dn in particular, and 10ac and 13ac to a lesser extent, upheld the principle that punctuation must not be ignored.
My one grumble was 4ac. Although I cannot find dictionary support for my original guess WALLOPED, there are so many words that mean “drunk” in UK English that I think it is unkind to the solver to use “Drunk” as one of the definitions in a double definition clue. I do not subscribe to the view that ambiguous clues are acceptable if the checked letters resolve the ambiguity.
Loved it, especially Chekhov, and coma (once I’d seen the blog. Fiendish!
I have no grumbles at all and also loved the puzzle. IDOLATER seems to be more common across the Atlantic.
Thanks to Goliath and Oriel.
Thanks Goliath for a superb crossword. My top picks included CANNON, DREARY, CHINCHILLA, AVERSION, and COMA. I had no issue with the ‘medical’ terminology since all of it was quite benign. Thanks Oriel for the blog.
Lots to enjoy from the jumpers’ favourite setter with the usual well-crafted surfaces.
I would have been disappointed not to have learnt a medical term in a Goliath/Philistine.
Thanks to setter and blogger!
Eileen @3,
In Hong Kong, you’ll find slivers of slithery snakes in soup, served as a winter warmer! 😉
I share Pelham Barton@9’s grumble about ‘drunk’ in 4a. I entered ‘battered’.
Otherwise a fun solve and I didn’t find any ‘obscurities’; I didn’t know ATOPIC, but the clue couldn’t have been more transparent.
Thanks Goliath and Oriel.
I appreciated the grid today with a preponderance of longer words, as I always get stuck on the short ones. Today I was defeated by COMA.
Does DEWLAP mean “with a double chin?” I thought it just meant a double chin. Indeed I see Chambers has DEWLAPPED or DEWLAPT as the adjectival form.
Thanks to Goliath and Oriel.
19dn: Collins 2023 p 549 also has dewlap only as a noun, with adjectives as given by Babbler@18. Perhaps “with” is meant as a connecting word by analogy with “and” in the double definition clue at 4ac.
No complaints from me, although I also got battered when I should have been getting hammered. These things happen.
This was fun and no I didn’t parse COMA, nor the piece of cake. IDOLATER was my favourite.
Thanks Goliath and Oriel