Functional Programming: Understand Functional Programming Terminology

Please anyone help me to identify which is a lamda function in this assignment…
there are three function i.e; prepareGreenTea, prepareBlackTea, prepareTea

This article (not mine) is what I thought lambdas were, moving from python:

map, reduce and filter are functions that apply a lambda to each value in an array and return a new value.
for example

let shortList = myList.filter(x => x.length >= 10)

a lambda (the arrow function) is passed in to the filter function.

the lambda returns true or false for each value in the array, and the filter pushes the true values in to a new array.

in the exercise you looked at, the lambdas are named prepareBlackTea and prepareBlackTea. They are passed in to the getTea function as the prepareTea argument.