what does "gash" here means?
—they're breaking camp.
—frightened little gashes.

I know it kind of points someone coward,but I can't even find the exact meaning of gash from wikipedia,I guess this word maybe is a local slang,right?

hi,@fdmaxey,here the text.
209
00:18:30,664 -- 00:18:31,864
They're breaking camp.

210
00:18:31,932 -- 00:18:33,299
Frightened little gashes,

211
00:18:33,367 -- 00:18:37,170
Running away with their cocks between their cheeks.

212
00:18:37,237 -- 00:18:38,171
Retreat would take them beyond

213
00:18:38,238 -- 00:18:40,206
the mountains to the north.

214
00:18:40,274 -- 00:18:42,041
Their torches bear west.

215
00:18:42,109 -- 00:18:43,643
West?

216
00:18:43,711 -- 00:18:45,878
They're swinging around to attack the villages below the pass.

217
00:18:48,148 -- 00:18:50,383
Our villages.

218
00:18:50,451 -- 00:18:52,185
Slippery little cunts.@Alex,no,they are not the gurls...LOL
they are Getas.

Question

what does "gash" here means?
—they're breaking camp.
—frightened little gashes.

I know it kind of points someone coward,but I can't even find the exact meaning of gash from wikipedia,I guess this word maybe is a local slang,right?

hi,@fdmaxey,here the text.
209
00:18:30,664 --> 00:18:31,864
They're breaking camp.

210
00:18:31,932 --> 00:18:33,299
Frightened little gashes,

211
00:18:33,367 --> 00:18:37,170
Running away with their cocks between their cheeks.

212
00:18:37,237 --> 00:18:38,171
Retreat would take them beyond

213
00:18:38,238 --> 00:18:40,206
the mountains to the north.

214
00:18:40,274 --> 00:18:42,041
Their torches bear west.

215
00:18:42,109 --> 00:18:43,643
West?

216
00:18:43,711 --> 00:18:45,878
They're swinging around to attack the villages below the pass.

217
00:18:48,148 --> 00:18:50,383
Our villages.

218
00:18:50,451 --> 00:18:52,185
Slippery little cunts.@Alex,no,they are not the gurls...LOL 
they are Getas.

Answer

Very simply, gash means girls here.  Calling them scared little girls.  Read on for explanation...

Gash is a VERY old, antiquated slang word for female genitalia, because it looks like a gash from a wound.  I would even say it's archaic (no longer used).

It actually came to mean girls because, like f###ers, it would commonly be used to refer to wimps, to emasculate.  So scared f###ers is the modern day version of scared gashes.

Cunts, used at the end, is the same thing:  female genitalia used to emasculate them, calling them girls (or people with cunts).

Answer

It's most likely a vulgar British slang.The frightened ones were the girls?

Answer

I'd have to know the context.
However, "gash" is a long cut.  You would get a gash from a knife or something sharp, like a stone.  If they are talking about a number of small cuts, this might be very frightening.
Do you have the complete text?

Answer

In this case, 'gashes' means girls, that is they were running away like frightened girls. Have a look at www.urbandictionary.com.  Both Alexs are correct.