Slipped

He slipped the pen off the desk and into his pocket.

The spy slipped the secret code into the message, without anyone realizing it.

The secret plan was slipped into a confidential memo, without anyone noticing.

She slipped and made an error in her calculations, resulting in an incorrect answer.

The package slipped from the delivery driver's hands and tumbled down the steps.

She slipped the coin from her pocket and dropped it into the slot machine.

The spy slipped past the guard and entered the building undetected.

His physical condition slipped after he stopped exercising.