LH

lh is a two-letter sequence that appears in various fields as an abbreviation or as a digraph, without one single, universal meaning. In biology and medicine, LH most commonly stands for luteinizing hormone, a gonadotropin produced by the anterior pituitary that regulates reproductive processes, including ovulation in females and testosterone synthesis in males. In neuroscience and anatomy contexts, LH is also used to denote the lateral hypothalamus, a brain region involved in feeding, arousal, and reward signaling.

In linguistics and orthography, lh appears as a digraph in certain languages. Notably in Portuguese, lh is used to spell a palatal consonant sound; the digraph occurs in words such as alho (garlic) and olho (eye). Pronunciation and specific phonetic realization can vary by dialect and language.

In practical writing, the meaning of lh is determined by context and capitalization. LH, in uppercase, often signals the hormone or the brain region, while lowercase lh may occur in notes, examples, or orthographic descriptions. Researchers and editors typically resolve ambiguity through explicit definition on first use or by relying on domain-specific conventions.

Overall, lh illustrates how two simple letters can carry distinct meanings across medicine, neuroscience, and language, reflecting the importance of context in interpreting abbreviations and digraphs.