Assumption
Expectation
noun, verbal noun
When you imagine something that's somewhat determined, that means you already have some sort of assumption or expectation about it.
想定 usually refers to assumptions made in advance about certain conditions or situations. It’s often used when talking about preparing for or anticipating future events, especially ones where planning might be required, like natural disasters.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
あの手がたくさんある神様の絵がここにかざられることを想定しています。
We assume the picture of the many-armed deity will be hung here.
まだ手に入れていないものを、手に入れたとの想定で行動するのは良くない。
It's not good to act on the assumption that you'll have something before you actually do.
地震を想定した避難訓練を行います。
We will now conduct the disaster drill assuming there is an earthquake.