Medical Terminology: Components and Plurals

Medical Terminology

• Medical terminology is a system of words and phrases used to describe the human body and its functions
• It consists of three components: prefix, root, and suffix
• Prefixes are placed at the beginning of the word and provide additional information
• Roots hold the most basic meaning of any word
• Suffixes are placed at the end of the word and provide additional information

Forming Plurals

• Medical and English rules for forming plurals:
  • a to ae (axilla - axillae, scapula - scapulae)
  • um to a (jejunum - jejuna, ileum - ilea)
  • us to i (thrombus - thrombi, alveolus - alveoli)
  • is to es (diagnosis - diagnoses, metastasis - metastases)
  • ma/oma to mata (sarcoma - sarcomata, carcinoma - carcinomata)
  • on to a (ganglion - ganglia, spermatozoon - spermatozoa)
  • yx, ax, ix to x + “es” (appendix - appendices, thorax - thoraces)
  • ex to i, x to c + “es” (vortex - vortices, cortex - cortices)
  • nx, s, x, ch, sh to x + “es” (larynx - larynges, pharynx - pharynges)
  • x to g + “es” (eye - eyes, vein - veins)
  • y (after a consonant) to i + “es” (artery - arteries, capillary - capillaries)
  • Lowercase abbreviations/acronyms add “s” with (‘) (rbc’s, wbc’s)
  • Uppercase abbreviations/acronyms add “s” without (‘) (OCPs, EEGs, ABGs)

Combining Forms and Pronunciation

• Combining forms: electrocardiogram
• Combining vowels and pronunciation rules
• Silent letters and unusual pronunciations:
  • ch - k
  • dys - dis
  • eu - u
  • gn - n
  • ph - f
  • pn - n

Prefixes and Suffixes

• Common prefixes:
  • AN-, A-
  • ECTO-, EXO-
  • INTRA-, AB-
  • ENDO-, NEO-
  • AD-, HEMI-, NULLI-
  • ANTE-, PRE-
  • HYPER-, PERI-
  • ANTI-, CONTRA-
  • HYPO-, POST-
  • BI-, DYS-
  • INFRA-, INTER-
  • RETRO-, TRANS-
• Common suffixes:
  • -AC, -IC, -AL, -OUS
  • -ATE, -IZE
  • -ECTOMY, -GRAM
  • -OLOGY, -GRAPH
  • -OMA, -GRAPHY
  • -ISM, -SCOPE
  • -OTOMY, -OSTOMY
  • -ENT, -ER, -IST
  • -ITIS, -PATHY
  • -GENIC, -OLOGIST
  • -PHOBIA, -SCOPY

Root Words

• Common root words:
  • ABDOMIN/O
  • ADEN/O
  • DORS/O
  • ENCEPHAL/O
  • ANTER/O
  • ARETRI/O
  • GASTR/O
  • HEMAT/O
  • AUDI/O
  • BRACHI/O
  • HIST/O
  • INTESTIN/O
  • LYMPH/O
  • MY/O
  • NEUR/O
  • OCUL/O
  • BRONCH/O/IO
  • CARCIN/O
  • CARDI/O
  • COL/O
  • CYT/O
  • DERM/A/O
  • OPTHALM/O
  • OPT/O
  • GYNEC/O
  • OR/O
  • PULMON/O
  • OT/O
  • THORAC/O
  • PATH/O
  • PHARMAC/O
  • VENTR/O

Body Structures

• Directional terms:
  • Anatomical position
  • Anatomical directions: anterior, medial, proximal, posterior, lateral, distal
  • Body planes: sagittal, frontal, transverse
• Body cavities:
  • Ventral cavity
  • Dorsal cavity
  • Abdominal regions: hypochondriac, epigastric, umbilical, inguinal
• Positions:
  • Lithotomy position
  • Fowler's position
  • Lateral recumbent or Sims' position
  • Supine position
  • Prone position
  • Trendelenburg's position
• Head and trunk regions (roots): CEPHAL/O, CERVIC/O, THORAC/O, ABDOMIN/O, CELI/O, LAPAR/O, LUMB/O, PERITON
• Extremities (roots): ACRO, BRACHI/O, DACTYL/O, PED/O, POD/O