Every word in isolation must have one primary stress. In longer words, there may be a secondary stress, which usually falls two syllables before the primary stress. For example (italicized are the secondary stresses, while only CAPS are the primary stress):
LEUcoPEnia
INsemiNAtion
MIcroSCOPic
PSYchoLOGical
In general, the stress is on the root of the word. For example:
disORder
biLATeral
conGENital
TUbule
reGULT
inHIBit
exCRETE
MEMbrane
FAILure
NOTE: Prefixes are usually weak as are Anglo-saxon endings. For example:
KINGdom
SCHOLarship
HANDsome
HOliness
Certain romance suffixes fix the stress in whatever word the are added to. The most frequent of these stress fixing suffixes are the following:
-ic fixes the stress on the preceding syllable. For example:
pediAtric
orthoPEdic
antibiOTic
nePHRITic
hyperDERmic
There are only 8 common exceptions:
CATHolic
HERetic
LUnatic
ARsenic
POLitics
aRITHmetic
ARabic
RHEToric
-ion fixes the stress on the preceding syllable:
contraCEPtion
gesTAtion
reACtion
abLAtion
dimiNUtion
perFUsion
But this is only a particular case of a much more general rule: Suffixes of the form ‘i/u + vowel’ fix the stress on the preceding syllable:
-ity fixes the stress on the preceding syllable. For example:
QUANtity
eQUALity
deFORMity
But this is again only a particular case of a general rule: Word stress nouns (mainly abstracts) ending with -y have antepenultimate stress (third syllable from the end):
A notable exception to this rule is words ending with -plasty, which is stressed:
orcheoPLASTY, rhinoPLASTY, mammoPLASTY
-itis, -osis, -esis are also stressed. For example:
dermaTItis
cirRHOsis
amniocenTEsis
These rules fixing the stress according to the suffix cause the position of the stress in a word to change in its derived form. In the table below, the words in column 2 have weak endings and keep the same stress as the root forms of column 1. In the 3rd and 4th columns, the words have stress-fixing suffixes with displacement of stress.