なかなか (nakanaka nai): Not easily or not for a long time
～なかなか (nakanaka nai)
Meaning
Not easily; not for a long time; quite
Formation and usage
なかなか + negative verb. In a separate positive use: なかなか + adjective, meaning quite or better than expected.
Explanation
With a negative verb, it describes something that does not happen easily or takes longer than hoped. With an affirmative adjective, it can mean quite or better than expected. The negative use is the focus of this entry.
Examples
バスがなかなか来ません。
The bus is taking a long time to come.
この漢字はなかなか覚えられません。
I cannot seem to memorize this kanji.
忙しくて、なかなか友達に会えません。
I am so busy that I rarely get a chance to see my friends.
昨日は心配でなかなか眠れませんでした。
Yesterday I was worried and could not get to sleep for a long time.
雨がなかなかやみません。
The rain shows no sign of stopping.
How related patterns differ
なかなか～ない describes a desired result that does not come easily. ず negates an action or means without doing, without itself implying a long wait. だらけ describes a state full of usually undesirable things, not a negative verb form.