stress

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Importance, significance, or emphasis placed on something. synonym: emphasis.
• noun The relative force with which a sound or syllable is spoken.
• noun The emphasis placed on the sound or syllable spoken most forcefully in a word or phrase.
• noun The relative force of sound or emphasis given a syllable or word in accordance with a metrical pattern.
• noun A syllable having strong relative emphasis in a metrical pattern.
• noun An accent or mark representing such emphasis or force.
• noun The internal distribution of force per unit area within a body subject to an applied force or system of forces.
• noun The internal resistance of a body to such an applied force or system of forces.
• noun A condition of extreme difficulty, pressure, or strain.
• noun A condition of metabolic or physiologic impairment in an organism, occurring usually in response to adverse events and capable of causing physical damage.
• noun A condition of psychological strain occurring in people and animals, usually in response to adverse events and capable of causing symptoms and signs such as increased blood pressure, insomnia, and irritability.
• noun A stimulus or circumstance causing such a condition.
• intransitive verb To place emphasis on.
• intransitive verb To give prominence of sound to (a syllable or word) in pronouncing or in accordance with a metrical pattern.
• intransitive verb Informal To subject to physiological or mental stress or strain. Often used with out.
• intransitive verb To subject to mechanical pressure or force.
• intransitive verb To undergo physiological or mental stress, as from working too much. Often used with out.

from The Century Dictionary.

• To straiten; constrain; press; urge; hamper.
• In mech., to subject to a stress.
• To lay the stress, emphasis, or accent on; emphasize.
• noun In electricity, electromotive force; difference of potential; pressure: as, a stress of 2000 volts.
• noun A stress in the direction opposite to the usual stress to which a piece in a structure is subjected. In this case the negative stress may be either tension or compression.
• noun Constraining, urging, or impelling force; constraining power or influence; pressure; urgency; violence.
• noun In mech., an elastic force, whether in equilibrium with an external force or not; the force called into play by a strain.
• noun Stretch; strain; effort.
• noun Weight; importance; special force or significance; emphasis.
• noun The relative loudness with which certain syllables or parts of syllables are pronounced; emphasis in utterance; accent; ictus.
• noun Relatively to another stress, a stress orthogonal to a strain perfectly concurrent with the other stress.
• noun Relatively to an infinitesimal homogeneous strain, a stress such that, if the strain be so compounded with a rotation as to produce a pure strain, the motions of the particles upon the surface of a sphere relatively to its center represent in magnitude and direction the components of the stress.
• noun Synonyms Accent, etc. See emphasis.
• noun Distress; difficulty; extremity; pinch.
• noun In law: The act of distraining; distress.
• noun A former mode of taking up indictments for circuit courts.

from the GNU version of the Collaborative International Dictionary of English.

• noun obsolete Distress.
• noun Pressure, strain; -- used chiefly of immaterial things; except in mechanics; hence, urgency; importance; weight; significance.
• noun (Mech. & Physics) The force, or combination of forces, which produces a strain; force exerted in any direction or manner between contiguous bodies, or parts of bodies, and taking specific names according to its direction, or mode of action, as thrust or pressure, pull or tension, shear or tangential stress.
• noun (Pron.) Force of utterance expended upon words or syllables. Stress is in English the chief element in accent and is one of the most important in emphasis. See Guide to pronunciation, §§ 31-35.
• noun (Scots Law) Distress; the act of distraining; also, the thing distrained.
• noun unusual exertion of the voice.
• noun constraint imposed by continued bad weather.
• noun to attach great importance to; to emphasize.
• noun to strain.
• transitive verb rare To press; to urge; to distress; to put to difficulties.
• transitive verb To subject to stress, pressure, or strain.
• transitive verb To subject to phonetic stress; to accent.