1.
If you are ~ to something, you know it so well or have experienced it so often that it seems natural, unsurprising, or easy to deal with.
I was ~ to being the only child at a table full of adults...
= used
ADJ: v-link ADJ to n/-ing
2.
When your eyes become ~ to darkness or bright light, they adjust so that you start to be able to see things, after not being able to see properly at first.
My eyes were becoming ~ to the gloom.
ADJ: v-link ADJ to n
3.
You can use ~ to describe an action that someone usually does, a quality that they usually show, or an object that they usually use.
He took up his ~ position with his back to the fire...
Freed acted with his ~ shrewdness.
...his ~ glass of whisky.
= usual, habitual
ADJ: poss ADJ n