Two-Way Communication System Outside One's Door
This page is the CodyCross answer for the clue below from Rainforest, Group 1211, Puzzle 3 (Caterpillar).
Question is: Two-Way Communication System Outside One's Door
and the answer is: INTERCOM
Word Meaning:
INTERCOM — An independent, telephonic communication system, set up around and throughout a building, complex, or residence, typically for access control.
Definitions from Wiktionary.