beta particleˈbeta ˌparticle noun [countable] technical 
an electron or positron that is sent out by some radioactive substances
an electron or positron that is sent out by some radioactive substances- instability
- install
- installation
- installment plan
- instalment
- instance
- instant
- instantaneous
- instantaneously
- instantly
- instant message
- instant messaging
- instant replay
- instead
- instep
- instigate
- instigation
- instigator
- instil
- instinct
- instinctive
- instinctively
- instinctual
- institute
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