'main trait' is correct and usable in written English.
You can use it to describe a key quality or attribute that someone or something is known for, especially when you are comparing them with others. For example, "The main trait of the new model is its durability."
To the visitor, this Baker's main trait would seem to be skill in scaring the beautifully costumed Warren Christopher away from a place called Tallahassee.
Lively's main trait is a lofty bearing that conveys a mild boredom, a distracted air of superiority that suggests that she places herself a little bit above the rest.
A sensitivity analysis was conducted to quantify the relative parameter influences on the main trait of interest, the grain yield.
The main trait of this free boundary problem is that it is essentially multidimensional, so that its well-posedness is hard to establish by using the usual methods in the classical theory of free boundary problems.
The qTSN4 generally stimulated secondary branch number, particularly in IRRI146 (both in GH and in the field), which appeared to be the main trait of panicle plasticity.
But others hold that the main trait selected for was friendliness--seeking human company and not biting--and that the cleverness of dogs was an unintended byproduct.
Not only are there just four crops, but they are still limited to two main traits introduced by genetic engineering: insect resistance and herbicide resistance.
The bottles are organized by simple adjectives describing their main traits: "juicy," "smooth," "big" and "sweet" for reds; "fizzy," "fresh," "soft" and "luscious" for whites.
It's called the Newcastle Personality Assessor (NPA) and it gives you a level for each of five main traits: extraversion, neuroticism, conscientiousness, agreeableness and openness.
Suspicion is said to be one of Mr Ivanishvili's main traits.Mr Ivanishvili's supporters and his opponents agree on one thing: he is not a natural politician.
On the evidence so far, one of its main traits will be the repression of dissent and the concentration of even more power in Mr Chávez's own hands.
