-cy

DEFINITION of -cy

-cy is an English noun-forming suffix, ultimately from Latin -tia/-cia, used to convert an adjective — most often one ending in -t, -te, or -tic — into an abstract noun naming the state, condition, quality, or degree of that adjective. In medical usage it appears in some of the most frequently charted descriptors of clinical status: pregnancy (state of being pregnant), malignancy (state of being malignant), latency (state of being latent, as in a dormant infection), patency (state of being open or unobstructed, as of a vessel or airway), potency (strength or effectiveness of a medication), and deficiency (state of lacking a substance, as with a nutrient or clotting factor). It functions purely as a grammatical, nominalizing suffix rather than a root carrying independent clinical meaning, so its clinical weight always comes from the adjective it attaches to — “malignant” versus “malignancy,” “latent” versus “latency.” It is easily confused with the unrelated suffix -cracy (Greek kratos, “rule, power,” as in “democracy”), and with process-forming endings like -sis (e.g., “necrosis”), which name an ongoing process rather than a static state or quality.

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ETYMOLOGY of -cy

latin

Component	Origin	Meaning
-cy	Latin -tia, -cia (via Old French -cie)	“state of,” “quality of,” “condition of” — abstract-noun-forming suffix

The suffix entered Middle English through Old French borrowings of Latin abstract nouns ending in -tia/-cia — words such as “clemency” (from clementia) and “constancy” (from constantia) arrived as whole units in the 14th–15th centuries. English speakers then extended the pattern productively, attaching -cy directly to native and semi-native adjectives ending in -t/-te/-nt to coin new abstract nouns without needing a matching Latin original — this is how “malignancy” was built from “malignant” and “pregnancy” from “pregnant.” The suffix remains one of the most productive noun-forming endings attached to Latinate adjectives in clinical English: pregnancy, latency, potency, patency, malignancy, efficacy, deficiency, consistency, urgency, frequency, and adequacy all follow the same pattern of adjective-plus--cy.

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🔗 RELATED TERMS

• pregnancy — the state of carrying a developing fetus; a normal, uncomplicated pregnancy encounter is coded under Z34.90, while incidental pregnant status noted during unrelated care is coded Z33.1
• latency — a dormant or inactive phase of a disease process; the clinically coded example is latent tuberculosis infection, coded Z22.7
• patency — the state of being open or unobstructed, as of a vessel, duct, or airway; patency itself isn’t coded — its loss (e.g., occlusion, stenosis) is the diagnosis actually captured
• urinary urgency — a sudden, compelling need to urinate; coded R39.15
• urinary frequency — abnormally frequent urination; coded R35.0
• deficiency — a nonspecific state of lacking a substance; the specific deficiency is what’s coded, e.g., vitamin D deficiency at E55.9
• malignancy — general term for a cancerous process; not independently billable, since the specific primary-site neoplasm code (e.g., a lung primary at C34.90-range) is what’s actually reported
• -cracy — an unrelated Greek-derived suffix (“rule, power”) frequently confused with -cy by surface resemblance only

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DERIVATIONS of -cy

TABLE definition AS Definition
FROM #medterm 
WHERE length(filter(roots, (word) => econtains([[-cy]].roots, word))) > 0 AND file.name != [[-cy]].file.name
SORT file.name ASC

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Query functionality

TABLE definition AS Definition
FROM #medterm 
WHERE length(filter(definition, (word) => econtains([[-cy]].definition, word))) > 0 AND file.name != [[-cy]].file.name

Med terms dictionary Appendix A Prefixes Appendix B Combining Forms Appendix C Suffixes Appendix D Suffix forms