腐朽 (fǔ xiǔ): 腐っている

The trunk of this old tree has already rotted; a light touch makes a large chunk of wood shavings fall off.

The wooden beams of that house are severely decayed. The engineer said they must be replaced immediately, otherwise there is a risk of collapse.

These fruits have been left too long and have already rotted, giving off an unpleasant smell.