nanika ＝something it is so hard to explain, but maybe i can say the Japanese language doesn't have the difference between transitive verbs and intransitive words. and when u want to use verbs as transitives,u have to use "o" or "ni" etc. for example... ★watashi wa taberu(i eat) →watashi wa ringo o taberu (i eat apple)

Well Im not Japanese and its in romaji and out of context, which makes it hard but my guess is its 何か at the beginning which means like what? not sure about the O at the end, maybe a sound of surprise. Can you give us the Japanese and the context you saw heard it?