1. the act of perceiving; observation; attention: to escape notice. 2. take notice to pay attention; attend. 3. take no notice of to ignore or disregard. 4. information about a future event; warning; announcement. 5. a displayed placard or announcement giving information.
Nicotine: A Stimulant Nicotine, the chemical that makes addicts out of cigarette smokers, is a stimulant with properties similar to those of cocaine and amphetamine (speed). Nicotine provides the pick-me-up that smokers feel.
Stimulants are chemicals that excite your central and/or peripheral nervous system. Excite, in this case, means to release more chemicals or send more/faster messages through your nervous and body. Most people think of stimulants in terms of illegal drugs, like cocaine.