Add “drain” to glossary

[sftim]

This is a Feature Request

What would you like to be added
Update https://kubernetes.io/docs/reference/glossary/ to explain the term “drain”

Explain the overall concept, and maybe also mention kubectl drain specifically. Remember that glossary entries need to be brief.

Why is this needed
drain is a jargon term and readers may not recognize it

Comments
/language en
/kind feature
/help
/triage accepted
/priority backlog

[k8s-ci-robot]

@sftim:
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In response to this:

This is a Feature Request

What would you like to be added
Update https://kubernetes.io/docs/reference/glossary/ to explain the term “drain”

Explain the overall concept, and maybe also mention kubectl drain specifically. Remember that glossary entries need to be brief.

Why is this needed
drain is a jargon term and readers may not recognize it

Comments
/language en
/kind feature
/help
/triage accepted
/priority backlog

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[iheartNathan]

/assign