You can hide a table... simply right click on the object and select Properties and then tick Hidden.
However... It would be remiss of me to not point out that all this does is hide it in the DB window... all you need to do is ... select Tools > Options and then click Show Hidden Objects and hey presto, they are back again.
Security in Access is, frankly, a whole big basket of snakes... though can be quite effective... if you want to secure your application then you need to, honestly, invest in a book on the subject... you will get loads of different suggestions from any forum on how to approach this... but ultimately your strategy needs to be tailored to your specific environment, development and users.
Of course, you may have already done this and realised that hiding the tables is all you need ;) ... in which case, fill yer boots.