S: (n) nitrogen, N, atomic number 7 (a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues)
S: (n) chemical element, element (any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter)
S: (n) substance (the real physical matter of which a person or thing consists) "DNA is the substance of our genes"
S: (n) matter (that which has mass and occupies space) "physicists study both the nature of matter and the forces which govern it"
S: (n) entity (that which is perceived or known or inferred to have its own distinct existence (living or nonliving))
S: (n) part, portion, component part, component, constituent (something determined in relation to something that includes it) "he wanted to feel a part of something bigger than himself"; "I read a portion of the manuscript"; "the smaller component is hard to reach"; "the animal constituent of plankton"
S: (n) relation (an abstraction belonging to or characteristic of two entities or parts together)