The most important reason behind a decision is an example of the foremost reason.
Was first and foremost a soldier.
The foremost researchers in the field.
The foremost ranks of the advancing warriors.
Kept the idea foremost in her mind.
Origin of foremost
- Alteration of Middle English formest first from Old English per1 in Indo-European roots
From American Heritage Dictionary of the English Language, 5th Edition
- From Old English formest, fyrmest (“earliest, first, most prominent”), from Proto-Germanic *frumistaz, from the locative stem *fur-, fr- + the superlative suffix *-umistaz. The suffix *-umistaz was a compound suffix, created from the rarer comparative suffix *-umô (as in Old English fruma) + the regular superlative suffix *-istaz (English -est). Cognate with Old Frisian formest, Gothic (frumists). See for, first and Old English fruma for more.