Real Dictionary

squid
countable noun: A squid is a sea creature with a long soft body and many soft arms called tentacles.

SQUID in American English
an electronic device for detecting and measuring very weak magnetic fields and currents, esp. the minute ones in and around the brain and heart
any of a number of long, slender, carnivorous cephalopod sea mollusks (esp. order Teuthoidea) having eight arms and two long tentacles: small squid are used as food and for fish bait
to take on an elongated squidlike shape due to strong air pressure
noun: any of several ten-armed cephalopods, as of the genera Loligo and Ommastrephes, having a slender body and a pair of rounded or triangular caudal fins and varying in length from 4–6 in. (10–15 cm) to 60–80 ft. (18–24 m)
noun: superconducting quantum interference device: a device that senses minute changes in magnetic fields, used to indicate neural activity in the brain

SQUID in British English
abbreviation for: superconducting quantum interference device

squid in British English 1
noun: any of various fast-moving pelagic cephalopod molluscs of the genera Loligo, Ommastrephes, etc, of most seas, having a torpedo-shaped body ranging from about 10 centimetres to 16.5 metres long and a pair of triangular tail fins: order Decapoda (decapods)

squid in British English 2
noun: a pound sterling