电话 (diànhuà) means telephone or phone call. It can refer to the device itself or the act of making a call. Common phrases include 打电话 (to make a phone call) and 电话号码 (phone number).
你的电话号码可以告诉我吗?
Nǐ de diànhuà hàomǎ kěyǐ gàosù wǒ ma?
Can you give me your phone number?
我刚才给你打了三个电话,你都没接。
Wǒ gāngcái gěi nǐ dǎ le sān ge diànhuà, nǐ dōu méi jiē.
I just called you three times and you didn't answer any of them.
他正在接一个很重要的电话,等一下再说。
Tā zhèngzài jiē yí ge hěn zhòngyào de diànhuà, děng yíxià zài shuō.
He's taking a very important call — let's talk later.