also: けども
conjunction, particle
Casual conjunction/particle used to connect contrasting statements or to soften a statement. Often used at the end of a sentence to imply hesitation or to leave a thought unfinished.
行きたいけど、時間がない。
I want to go, but I don't have time.
ちょっとお願いがあるんだけど…
I have a small favor to ask, but…