Freddy Krueger's locale: Abbr.

ELMST

Think of the tree-lined street where nightmares begin in Springwood.

This clue refers to Freddy Krueger, the iconic villain from the Nightmare on Elm Street horror movies. His "locale" is Elm Street, where he terrorizes victims in their dreams, and "Abbr." signals that the answer is shortened. The full name "Elm Street" is condensed to "ELMST" by dropping the "reet" and keeping the first letters of each word.