Broader definitions of chemicals or chemical substances can be found, for example: the term 'chemical substance' means any organic or inorganic substance of a particular molecular identity, including â (i) any combination of such substances occurring in whole or in part as a result of a chemical reaction or occurring in nature.
The major groups of worms include various species of flatworm, annelid, ribbon worm, spiny-headed worm, and aschelminth. Worms typically have an elongated, tubelike body, usually rather cylindrical, flattened, or leaflike in shape and often without appendages.
Some insects have adopted the worm name including inchworms, glowworms and silkworms, but they do not have the characteristics of an actual worm. A commonly known worm is the earthworm, which is found in gardens and most backyards. Its tubular body and lack of legs, antennae or proper body segments is descriptive of all types of worms, although some worms do have mouths.