noun which may take the genitive case particle 'no'
what little one has; meager; paltry
Emphasizes that the amount is very small and precious; often used with nouns like お金, 貯金, 時間, or 知識. Conveys a sense of 'the only little bit I have'.
なけなしのお金でパンを買った。
I bought bread with what little money I had.
なけなしの休みを利用して旅行に行く
I'm going on a trip using my meager vacation days.
わずか simply means 'a little' or 'few' and is neutral, while なけなし emphasizes that the small amount is all one has and is therefore precious or insufficient.
Derived from 無し (なし, 'not exist') with an emphatic or adverbial element け; the exact derivation is uncertain. The form なけなし literally suggests 'there being none', evolving to mean 'the only little bit that exists'.