uttermost

of the greatest possible degree or extent or intensity; "extreme cold"; "extreme caution"; "extreme pleasure"; "utmost contempt"; "to the utmost degree"; "in the uttermost distress"

(comparatives of `far'') most remote in space or time or order; "had traveled to the farthest frontier"; "don''t go beyond the farthermost (or furthermost) tree"; "explored the furthest reaches of space"; "the utmost tip of the peninsula"

the greatest possible degree; "he tried his utmost"