1
general::
Phrase(s): first and foremost
Cliché first to be dealt with and most important. • First and foremost, I think you should work harder on your biology. • Have this in mind first and foremost: Keep smiling!
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Also, first of all. Most important, primarily; also, to begin with. For example, First and foremost, I want to thank our sponsors, or What we need, first and foremost, is a new secretary, or We have to deal, first of all, with the early history. The first term, dating from the late 1300s, is redundant, since first and foremost mean virtually the same thing. Both it and the variant, which dates from the mid-1500s, are used to give emphasis to the initial item in a list of several. Also see FIRST OFF; FIRST THING.
American Heritage Idioms