n.

a fee charged in advance to retain the services of someone

同義詞：consideration

a person working in the service of another (especially in the household)

同義詞：servant

a dental appliance that holds teeth (or a prosthesis) in position after orthodontic treatment

Clinical experience with direct-bonded labial retainers
Long-term experience with direct-bonded lingual retainers.
Device container assembly with adjustable retainers for a reticle
BLOCK WALL CONSTRUCTION SYSTEM INCLUDING USE OF CLIP RETAINERS
Correcting malaligned mandibular incisors with removable retainers.
Marginal and internal fits of fixed dental prostheses zirconia retainers
Method of stent retention to a delivery catheter balloon-braided retainers
Etched castings: an improved retentive mechanism for resin-bonded retainers.
A 3-year follow-up study of various types of orthodontic canine-to-canine retainers
Stress distribution and abutment tooth mobility of distal‐extension removable partial dentures with different retainers: an in vivo...