HOH

HOH is an acronym used in several distinct contexts, and its meaning depends on the field in which it appears. The most common references are in chemistry, tax terminology, and accessibility.

In chemistry, HOH is a conventional way to denote a water molecule, written as H–O–H to emphasize the two hydrogen atoms bonded to a central oxygen atom. This notation is often used in structural diagrams and computational chemistry to reflect the bent geometry of water, with an H–O–H bond angle of about 104.5 degrees. It helps avoid implying a linear arrangement and is encountered in discussions of molecular structure and behavior of water.

In United States federal income taxation, HOH stands for Head of Household, a filing status for unmarried taxpayers who provide a qualifying dependent and maintain a household for more than half the year. This status generally yields a higher standard deduction and more favorable tax brackets than the single filing status. Eligibility requires that the taxpayer be unmarried (or considered unmarried), pay more than half the household costs, and have a qualifying person living with them for more than half the year, among other requirements.

HOH is also used as an abbreviation for hard of hearing, a term used in medical, educational, and accessibility contexts to describe individuals with significant hearing loss who may rely on amplification, assistive devices, or other accommodations.

These meanings illustrate how HOH can denote a chemical representation, a tax filing status, or a disability-related term, depending on the context.