嫌疑

The essay is suspected to be a plagiarism.

He was detained for seven days upon a mere suspicion.

suspicion of corruption

turn suspicion (towards)

arouse/cause suspicion

lay oneself open to suspicion

be suspected of being guilty

be suspected of murder/robbery/theft; be under suspicion of murder/robbery/theft

be arrested under suspicion

dispel/remove suspicion

be clear from suspicion

be beyond/above suspicion