What does it mean when someone writes 드림 at the end of an email? Does it have a specific meaning in that context?
드림 is a noun form of 드리다 which means to 'give' (polite form of 주다). It is usually used when juniors or subordinates write a letter or e-mail to their seniors or elders. For example, it is used when a student writes a letter to their teacher or a salesperson writes one to their clients.
You could also use '올림" which is a noun form of 올리다 which literally means to 'raise' or 'lift'.
One thing you need to note is you don't use them between colleagues or friends and you should use '씀' (which is a noun form of '쓰다 (write)') instead.
'드림' and '올림' are polite forms of '씀'.