easier: costing less effort than the other thing it is being weighed against
This word is a comparison, never a description. It does not say that something is easy; it says only that one thing takes less effort than another thing named alongside it. It is built from "well" joined to a word for wearying labor (κόπος), so the picture behind it is a job that costs less sweat, not a job that is simple or uncomplicated.
All seven times it appears, it sits in the same shape: two options set side by side with "than" between them. Three times Jesus asks a crowd which of two things is easier, and the point of the question is that saying something and doing something visible are not equally easy to check. The other four times he states outright which of two things is easier, and the thing he puts on the easier side is itself impossible.
That second use is a way of saying "never" without using the word. A camel does not fit through a needle, and heaven and earth do not pass away. Putting the impossible on the lighter side of the scale pushes whatever sits on the other side out of reach altogether, or, in the case of the law, past any chance of failing. The same conversation about the rich man reaches for a word for what is hard to manage (δύσκολος) and then for the word for what simply cannot be done (ἀδύνατος), which shows how this word sits between them: it ranks difficulty rather than naming it or denying it outright.