Definitions:
a long-bodied predatory freshwater fish with a pointed snout and large teeth, of both eurasia and north america.

an infantry weapon with a pointed steel or iron head on a long wooden shaft.

(in names of hills in the lake district) a hill with a peaked top

kill or thrust (someone) through with a pike

a jackknife position in diving or gymnastics.

withdraw from or go back on (a plan or agreement).

let (someone) down.