OSX Mail - deleting imap email without deleting on gmail server I am using Mail.app to access my gmail account (business / google apps email). 

I want to delete a big pile of emails in Mail to clean up my inbox, but I want to keep those emails in gmail (IMAP server) so I look them up in the future by logging directly into gmail. 

I'm new to Mail. Is there a setting where I can delete my emails in this account freely in Mail without deleting them at all from the gmail?
You can check Mailbox Behaviors in your Gmail account setting (under Accounts) and check Store deleted messages on the server. This will make your messages still available in other clients even if you delete them in the Mac where you have this setting.

Reference: Mail (El Capitan): Mailbox Behaviors preferences