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might 1 (mīt)
1. Great power or force, as of a nation or army.
2. Physical strength: Push with all your might! See Synonyms at strength.

[Middle English, from Old English meaht, miht; see magh- in the Appendix of Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
might 2 (mīt)
aux.v. Past tense of may
a. Used to indicate a condition or state contrary to fact: She might help if she knew the truth.
b. Used to express possibility or probability: It might snow tomorrow.
2. Used to express possibility or probability in the past: She thought she might be late, but she arrived on time.
3. Archaic Used to express permission in the past: The courtier was informed that he might enter the king's chambers.
4. Used to express a higher degree of deference or politeness than may, ought, or should: Might I express my opinion?

[Middle English, from Old English meahte, mihte, first and third person sing. past tense of magan, to be able; see MAY1.]

Usage Note: May or might? In many situations, the choice between these two verbs can be clarified by remembering that might is the past tense form of may, and that in English, a past tense form is used to refer not just to events that occurred in the past (She left yesterday), but to hypothetical, counterfactual, or remotely possible situations (If you left now, you'd get there on time.) Thus, the past tense form might is appropriate in this sentence about a future event that is a remote possibility: If I won the lottery, I might buy a yacht, which contrasts with the present-tense version that indicates an open possibility: If I win the lottery, I may buy a yacht. When referring to a hypothetical or contrary-to-fact situation in the past, rather than an imagined future situation, the verbs are shifted to the remote past: won becomes had won, and might buy becomes might have bought: If I had won the lottery, I might have bought a yacht. Since about the 1960s, however, people have started using may have where might have would be expected (as in, If he hadn't tripped, he may have won the race). Although this usage is common in casual speech, it is considered unacceptable by the majority of the Usage Panel. In our 2012 survey, 97 percent of the Usage Panelists found the sentence If John Lennon had not been shot, the Beatles might have gotten back together acceptable. Only a third of the Panel (32 percent) approved of the same sentence with may have replacing might have. Using may have for a past counterfactual situation instead of might have is not only frowned upon by the Panel but can also lead to confusion, since may have is best suited for a different kind of situation: present uncertainty about a past situation. Keeping the two forms distinct reduces ambiguity. He may have drowned, for example, is best used to mean that it is unknown whether the man drowned, not that the man narrowly escaped drowning. · When may and might are used to indicate possibility or probability, as in He may lose his job or We might go on vacation next year, the two words are used almost interchangeably. It is sometimes said that might suggests a lower probability than may, perhaps because of its use in hypothetical statements that omit the conditional clause (You might get there on time can be thought of as short for If you hurried, you might get there on time). In practice, however, few people make this distinction.

Our Living Language In many Southern US varieties of English, might can be paired with other auxiliary verbs such as could, as in We might could park over there. Words like might and could are known as modals, since they express certain "moods" (for example, I might go indicates an uncertain mood on the part of the speaker). Combinations such as might could, might would, and might can are known as double modals. Other less common combinations include may can, may will, and might should. Since double modals typically begin with may or might, they lessen the degree of conviction or certainty (much like the word possibly) more than a single modal does. Double modals are used, for example, to minimize the force of what one is saying, as when asking someone for a favor or when indicating displeasure. · Although double modals may sound odd outside of the South, they carry little if any social stigma within the South and are used by speakers of all social classes and educational levelseven in formal instances like political addresses. Like many features of Southern varieties of English, the use of double modals is probably due to the fact that many of the first English speakers in the South were Scotch-Irish, whose speech made use of double modals.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.