1. In a startling manner.

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

• startingly,
• sparklingly,
• startlingy,
• atartlingly,
• ztartlingly,
• xtartlingly,
• dtartlingly,
• etartlingly,
• wtartlingly,
• srartlingly,
• sfartlingly,
• strartlingly,
• startligly,
• starltingly,
• startlinglly,
• stagglingly,
• staelingly,
• smartyngly,
• Scintlingly,
• pantlingly

• starting line,
• start out,
• startling,
• stratify,
• struthionidae,
• Stratton,
• stretchiness,
• stretching,
• starting post,
• struthio,
• starting time,
• straiten,
• starting block,
• starting,
• stratman,
• startled,
• starting gate.

The adjective form of "startlingly" is "startling".

The plural form of the word "startlingly" does not change. It remains the same.

The singular form of the word "startlingly" does not exist as it is already in the adverb form.