Plural of bach; small vacation cottages or holiday homes, particularly in New Zealand and Australian English.
From bach, possibly from bachelor (as in bachelor pad) or from Welsh bach meaning small. In New Zealand and Australia, a bach or crib is a modest, informal holiday dwelling, different from the formal family home.
The bach perfectly captures how colonists' slang evolved differently—Kiwis and Aussies needed a word for those tiny throwaway holiday shacks, and they grabbed bachelor (the least-formal male living situation) to describe them, which is exactly how slang works: take what you've got and stretch it sideways.
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