Though its constituting elements (as given in Etymology above) may not be obvious for native speakers due to lexicalization, it is considered as having two elements for the purposes of spelling. Thus if another (third) compound element is added and the resulting number of syllables (excluding any inflectional suffixes and the adjective-forming suffix -i) exceeds six, a hyphen is inserted between the two main elements (e.g. {{{1}}}). Compounds with up to six syllables are spelled with no hyphen (e.g. {{{2}}}); see also below. For more, see the syllable-counting rule in Wikipedia.
Use this template in the ===Usage notes=== section of pages for explanation about the spelling of its compounds.
See at műszer.