a dime a dozen

A dime a dozen means: So common as to be practically or almost worthless.. It is mainly Australian English and may not be understood outside that context. There is no real cause for parental concern; it is descriptive vocabulary rather than risky behaviour. If your teen uses it, context will usually make the intent clear. A short, curious question about where they heard it is usually all that is needed to know whether to follow up.

a dime a dozen means: So common as to be practically or almost worthless.. Register: informal, Australian English. Often not understood outside its region; gloss the word on first use when writing for an international audience. A common learner mistake is using the word in a register it does not fit, or assuming a single global meaning; native speakers immediately notice when slang appears in formal contexts, so always check the surrounding register before producing it yourself.