This is the 1896th most frequent Russian word.
последней
The Russian word "последней" means "last" or "final" (feminine singular instrumental/genitive/dative form).
In this sentence, 'последней' is in the instrumental case of the feminine singular adjective, modifying 'главе' (chapter). It implies 'the last one in order'.
В последней главе много интересной информации.
The final chapter contains a lot of interesting information.
Here, 'последней' is in the instrumental case, describing 'она' (she) as 'the last one in a sequence'.
Она оказалась последней в очереди.
She turned out to be the last in line.
In this sentence, 'последней' is in the instrumental case, modifying 'надеждой' (hope). It expresses 'the last or final' in a figurative sense.