''inch'' అనే ఆంగ్ల పదము uncia నే లాటిన్ పదం నుండి ఉద్భవించినది. లాటిన్ భాషలో దీని అర్థము "పన్నెండవ భాగము"(అనగా ఒక అడుగు పొడవులో పన్నెండవ భాగము): ఔన్స్ అనుపదం కూడా ఇదేవిధంగా (పౌండులో పన్నెండవ భాగం) ఉధ్బవించినది.
The English word ''inch'' comes from Latin ''[[uncia (length)|uncia]]'' meaning "one-twelfth part" (in this case, one twelfth of a foot); the word ''[[ounce]]'' (one twelfth of a troy pound) has the same origin. The vowel change from ''u'' to ''i'' is [[Germanic umlaut|umlaut]]; the consonant change from ''c'' (pronounced as ''k'') to ''ch'' is [[palatalization|palatalisation]] (see [[Old English phonology#Distribution of velars and palatals|Old English phonology]]).
In some other languages, the word for "inch" is similar to or the same as the word for "thumb"; for example, {{lang-ca|polzada}} inch, ''polze'' thumb; {{lang-fr|pouce}} inch/thumb; {{lang-it|pollice}} inch/thumb; {{lang-es|pulgada}} inch, ''pulgar'' thumb; {{lang-pt|polegada}} inch, ''polegar'' thumb; {{lang-sv|tum}} inch, ''tumme'' thumb; {{lang-nl|duim}} inch/thumb; {{lang-sk|palec}} inch/thumb; {{lang-hu|hüvelyk}} inch/thumb, [[Danish language|Danish]] and {{lang-no|tomme}} / ''tommer'' inch/inches and ''tommel'' thumb.
Given the etymology of the word "inch", it would seem that the inch is a unit derived from the foot unit in Latin in Roman times.
