Serious
Terrible, Very, Difficult, Hard, Hectic
adverb, な adjective
A big change is a really serious thing. And people don't like change, either, making it a terrible event.
Also, in more recent history this has come to mean very as well.
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.
中々大変
rather difficult, rather serious
とても大変
very difficult, very serious
かなり大変
considerably difficult, considerably serious
大変な事
a difficult matter, a serious matter
大変な作業
an arduous task
大変な問題
a serious problem
大変お世話になる
to be much obliged to someone for their help
大変重要
incredibly important
大変失礼
very rude
日本語を習とくするのは大変ですが、がんばってくださいね。
Acquiring Japanese is difficult, but do your best!
大変丈夫な子供が生まれました。
They had a very healthy child.
災害時は、電話回線もネット回線も混み合って、繋がりづらくなるので、ブログの更新が大変です。
When there's a disaster, the phone and Internet circuits are overloaded and it gets hard to connect to them, so it's difficult to upload new blog posts.