conventional

adj

1. Pertaining to a convention, as in following generally accepted principles, methods and behaviour.

   “A “moving platform” scheme[…]is more technologically ambitious than maglev trains even though it relies on conventional rails. Local trains would use side-by-side rails to roll alongside intercity trains and allow passengers to switch trains by stepping through docking bays.”

   “Young-White’s paeans to short kings encourage us to confront society’s overvaluation of men’s height, and recognize the guys under 6ft whose positive attitudes render them nothing short of regal. A short king isn’t just any male-presenting person of modest stature – it’s someone who has the strength of character to flourish in the face of conventional male beauty standards.”

2. Ordinary, commonplace.

   “They wear conventional clothes, eat conventional food, and keep conventional hours.”

   ““You’re not conventional?” Isabel gravely asked. “I like the way you utter that word! No, I’m not conventional: I’m convention itself. You don’t understand that?””

   “Mother[…]considered that the exclusiveness of Peter's circle was due not to its distinction, but to the fact that it was an inner Babylon of prodigality and whoredom, from which every Kensingtonian held aloof, except on the conventional tip-and-run excursions in pursuit of shopping, tea and theatres.”

   “The history of our study of our solar system shows us clearly that accepted and conventional ideas are often wrong, and that fundamental insights can arise from the most unexpected sources.”

3. Banal, trite, hackneyed, unoriginal or clichéd.
4. Pertaining to a weapon which is not a weapon of mass destruction.
5. Making use of synthetic fertilizers and pesticides.
6. In accordance with a bidding convention, as opposed to a natural bid.

noun

1. A conventional gilt-edged security, a kind of bond paying the holder a fixed cash payment (or coupon) every six months until maturity, at which point the holder receives the final payment and the return of the principal.