Certain keyword not appearing in SERP but still in google index

[mavvy]

I have a strange encounter since Sunday.

One of my keyword not appearing in search. suddenly gone from pos 120+- to outer space. It is still in google index upon site: searches.

My other keywords still appearing in google serps.

Anybody encounter such scenario?

[Martijn_Scheijbeler]

I've seen this before, it's mostly because the rankings in the range of rank: 100+ are very likely to change often as the ranking over there is mostly based on small differences in ranking factors. I would recommend the page you're targeting to check it to be sure. But if the rest of your site is not showing any differences I wouldn't worry to much about that.

[mavvy]

Thanks for your replies. I discovered it has dropped from 120 to 249.. any likely cause ?

such a big drop is not normal to me. past few months has been steadily 110-130 pos..