How can I sent an email to a large distribution list without the recipients seeing all the email addresses.?

Put the email addresses in BCC (Blind carbon copy)

each recipient will only see there own address's come up with no idea of whom else or how many people you have sent to,

i don't really use the yahoo email, but it is set up on my outlook.. anyways if you use that Put all the distributions list in the BCC field.. that way one can see who else its been sent to

Use the Blind Carbon Copy address line. (BCC)

use the "bcc" recipient box and no one can see the other recipients

Put addresses in BCC field. (Blind carbon copy)