retainer has definitions from the fields of work,business,dentistry
1
[ noun ] (business) a fee charged in advance to retain the services of someone

Synonyms

consideration

Related terms

fee quid

2
[ noun ] (dentistry) a dental appliance that holds teeth (or a prosthesis) in position after orthodontic treatment

Related terms

dental_appliance

3
[ noun ] (work) a person working in the service of another (especially in the household)

Synonyms

servant

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