What are disinfectants? Give one example.

Hint: These are not suitable to be applied to the living tissue. They have the same functions as that of Antiseptics. These are mostly used for cleaning the floor, drains, etc.

Complete answer:
Disinfectants are chemical substances (i.e., antibacterial) which kill microorganisms but are not safe to be applied on the living tissue. These are generally used to kill microorganisms present in the drains, toilets, floor, etc.
The same substance can act as an antiseptic as well as a disinfectant depending upon the concentration of the solution used. For example, a $0.2%$ solution of phenol acts as antiseptic whereas a $1%$ solution acts as a disinfectant. Similarly, a low concentration of $S{{O}_{2}}$ is used for sterilizing squashes for preservation but a high concentration of the gas can be used as a disinfectant for living rooms when infected with bacteria and disease-carrying germs.
A few examples of disinfectants and antiseptics are:
A low concentration of chlorine, i.e., 0.2 to 0.4 parts per million (ppm) is used for sterilization of water to make it fit for drinking purposes, but a higher concentration of chlorine acts as disinfectants like chlorine bleach. It is the most cost-effective bleach.
Alcohols are also used as disinfectant and antiseptic.
Some other examples of disinfectants are quaternary ammonium salts, thymol, chlorine dioxide, formaldehyde, etc.

Note:
Antiseptics are the chemical substances (i.e., antibacterial) which prevent the growth of micro-organism and may even kill them. They are safe to be applied to living tissue. They are generally applied in wounds, cuts, ulcers, and diseased skin surfaces.