1. generally; mainly; usually; normally; mostly; for the most part
日曜日は大概家にいます。I'm usually at home on Sundays.
2. nearly all; almost all; most
泣いて謝れば大概のことは許してもらえます。If you cry and apologize, you'll be forgiven for most things.
3. gist; summary; outline; main idea
4. staying within bounds; not overdoing (something); not getting carried away; not going too far; being moderate
二人とも、調子に乗るのも大概にな。Don't get too carried away, you two.
5. probably; perhaps; in all likelihood
大概そんなことだろうと思った。I figured it was probably something like that.
6. considerably; greatly; really
あなたも大概失礼ですね。You're pretty rude yourself, aren't you?