English definition of “sincere”
› honest and saying or showing what you really feel or believe: He seems to be sincere. → Opposite insincere
sincere apologies/thanks, etc formal › used to add emphasis when you are expressing a feeling: The family wishes to express their sincere thanks to all the staff at the hospital. sincerity
/sɪnˈserəti/ noun [U] › No one doubted his sincerity.