siren

As a noun book is

book.

As a noun chime is

(musical instruments) a musical instrument producing a sound when struck, similar to a bell (eg a tubular metal bar) or actually a bell often used in the plural to refer to the set: the chimes or chime can be a chine; the edge of a cask.

As a verb chime is

to make the sound of a chime.

As a noun gorgon is

.

As a noun megaphone is

.

As a letter x is

the twenty-fourth letter of the.

As a symbol x is

voiceless velar fricative.

As a proper noun kraken is

(norse mythology) a colossal sea monster that attacks ships and sailors, often portrayed as a giant octopus or squid.

As an adjective false is

(label) one of two states of a boolean variable; logic.

As a noun stern is

a star; a small luminous dot that can be seen on the night sky.

As an adjective undefined is

lacking a definition or value.