1. Without the knowledge of others; privately.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• secruly,
• secruely,
• secertly,
• secrutiy,
• secretaty,
• spearetly,
• secrity,
• seppretly,
• sepratly,
• securerly,
• secrett,
• secterly,
• sepritly,
• secrety,
• secretivly,
• secrerty,
• secreity,
• seceretry,
• separetly,
• secretray

• secretaire,
• secretor,
• secretariat,
• Secretory,
• sea cradle,
• secretase,
• secreter,
• secretion,
• secret plan,
• Secreting,
• secretin,
• secretive,
• secretarial,
• secret,
• secured,
• secretary,
• secretively,
• secrete,
• secret code.

The adjective form of the word "secretly" is "secret".

The plural form of the word "secretly" is "secretly". The word does not change in its plural form.

The singular form of the word "secretly" is "secretly". The word does not change when it comes to singular or plural usage.