> 彼女は食【しょく】が細い【ほそい】。  
>  _She eats very little._

Does 細い have that meaning in that context?
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2017-06-01T02:46:15.330
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2017-06-01T06:12:09.003
2017-06-01T03:23:04.937
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meaning
Meaning of 細い in 彼女は食が細い
If you search in the dictionary for a meaning of 細い that fits, you probably
will not find any. 食が細い is an expression. And if you search for it in a
dictionary like jisho as a whole, you will get the definition :

> eating only a little; having a small appetite

As a side note, 細い{こまい}, can mean stingy, so it might be funny to imagine
someone being stingy with their food.

But your interpretation was the correct one.
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2017-06-01T02:56:14.390
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2017-06-01T02:56:14.390
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I don't know the etymology of 食｛しょく｝が細{ほそ}い. But it sounds that the path to
convey food to the stomach is narrow (細{ほそ}い) and the capacity of the stomach
is small, so he/she eats a little and/or feels full soon, and as a matter of
course he/she has a small appetite.

As for the antonym, you don't say 食｛しょく｝が太｛ふと｝い, but say like:  
- 彼｛かれ｝は大｛おお｝食｛ぐ｝いだ。  
- 彼｛かれ｝は大｛おお｝食｛ぐ｝らいだ。  
- 彼｛かれ｝は大｛たい｝食｛しょく｝漢｛かん｝だ。
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2017-06-01T03:33:18.067
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2017-06-01T03:42:37.837
2017-06-01T03:42:37.837
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Yes. 細い means thin. So yeah basically the amount she eats is very little.
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2017-06-01T06:12:09.003
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2017-06-01T06:12:09.003
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