basic, central, core, critical, crucial, essential, fundamental, important, integral, key, main, major, necessary, primary, principal, significant, vital
minor
active
common
The researchers discovered a common component in all types of the organism.

standard
Our software is becoming a standard component of many computer systems.

individual, separate, simple
Individual components for the car can be very expensive.

chemical, genetic
electrical, electronic
structural
aircraft, engine, etc.
course
off-the-shelf

add, include, incorporate, install, integrate
design
assemble
manufacture

failure
Component failure was the cause of the accident.

manufacturer, supplier

component in
a crucial component in our success.

Component is used with these nouns:
part