noun: a set of connected things or parts forming a complex whole, in particular.
a set of things working together as parts of a mechanism or an interconnecting network.
plural noun: systems
"the state railroad system"
synonyms: structure, organization, arrangement, complex, network;
informal: setup "a system of canals"
noun: engineer; plural noun: engineers
- a person who designs, builds, or maintains engines, machines, or public works.
synonyms: originator, deviser, designer, architect, inventor, developer, creator; mastermind
"the prime engineer of the approach"
verb: engineer; 3rd person present: engineers; past tense: engineered; past participle: engineered; gerund or present participle: engineering
- design and build (a machine or structure).
"the men who engineered the tunnel"
Thus, a Systems Engineer is a person who designs, builds, or maintains a set of connected things or parts forming a complex whole. Doesn't matter if that complex whole is a rocket ship, an airplane, a computer network, or a waste treatment facility. The Systems Engineer is the guy that makes things work.
Think of the classic "glass half full, glass half empty" test for optimism/pessimism. Any engineer can tell you the problem isn't half full or half empty. The problem is that the volume of the glass is twice a much as it needs to be to efficiently contain the liquid. The Systems Engineer is the guy who comes up with a way to successfully reduce the volume of the glass so it works properly, with maximum efficiency.
While the liquid is still in it.
And while people (customers) continue to drink out of it.
Which is why "Freakin' Awesome" should be a perfectly acceptable job title.