Nearsightedness
Shortsightedness, Myopia
When you can look at things that are near well but you can't see things far away, you have nearsightedness. Good to get those eyes checked out occasionally.
きんし
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
私は近視と乱視の両方があります。
I have both nearsightedness and an astigmatism.