Gasbag
Part of speech: noun
Definition: A bag or bladder to hold a reservoir of gas, as in a hot-air balloon. Metaphorically, a person who is overly garrulous or prone to making empty, unsupportable statements.
Envelope
Part of speech: noun
Definition: A paper or cardboard wrapper used to enclose small, flat items, especially letters, for mailing.Something that envelops; a wrappingA bag containing the lifting gas of a balloon or airship; fabric that encloses the gas-bags of an airshipA mathematical curve, surface, or higher-dimensional object that is the tangent to a given family of lines, curves, surfaces, or higher-dimensional objects.A curve that bounds another curve or set of curves, as the modulation envelope of an amplitude-modulated carrier wave in electronics.The shape of a sound, which may be controlled by a synthesizer or sampler.The information used for routing an email that is transmitted with the email but not part of its contents.An enclosing structure or cover, such as a membrane.The set of limitations within which a technological system can perform safely and effectively.
Example sentence: I'm in competition only with myself, and I always want to push the envelope.