retainer
UK: rɪˈteɪnə | US: rɪˈteɪnər
n. a person or thing that retains or keeps something in place
n. a fee paid to secure services, especially for a professional (e.g., lawyer)
n. a dental or medical device used to hold teeth or tissues in position
The word "retainer" traces back to Latin retinēre, combining re- (expressing repetition or backward motion) and tenēre (to hold). In Middle English, it evolved to describe a servant or attendant who "held" a position in a household, later extending to legal and medical contexts where something is "held" in place (e.g., fees, dental devices). The logic reflects physical or metaphorical retention.
The lawyer required a $5,000 retainer before taking the case.
She wore a dental retainer to align her teeth after braces.
Medieval knights often had loyal retainers in their service.
The company paid a retainer to the consultant for ongoing advice.
The retainer clip kept the cables neatly organized.