"Sliammon" (village) adopted 31 December 1945 on C.3561, as labelled on BC Lands map #20, 1912. Form of name changed to Sliammon (settlement) 3 January 1967 on 92F/15. Further changed to Sliammon (community). Name changed to Teeshohsum (community) per the provisions of the Tla'amin Treaty, Appendix W-2, effective 5 April 2016. Spelling changed 5 April 2025 to t̓ɩšosəm (community) on map 92F/15, as requested by Tla'amin Nation, 2024.

Source: BC place name cards, or correspondence to/from BC's Chief Geographer or BC Geographical Names Office

t̓ɩšosəm is a word in the ʔayʔajuθəm language, belonging to ɬaʔamɩn (Tla'amin), ƛoʔos (Klahoose), χʷɛmaɬku (Homalco) and k’ómoks (K'omoks) people (information provided by Tla'amin Nation, 2025).

Source: included with note

t̓ɩšosəm was formerly known as Sliammon Indian Reserve I.R. 1. The name t̓ɩšosəm  translates to “waters milky white with herring spawn” which was a descriptor of the abundance of this important resource to the people in the surrounding ancient village situated around the bay. Herring once accounted for up to 90% of ɬaʔamɩn people's diet [https://www.aptnnews.ca/national-news/tlaamin-nation-herring-spawn-british-columbia/]. t̓ɩšosəm is currently the main village site for the Tla'amin people and includes numerous culturally and spiritually significant sites. t̓ɩšosəm is the original name given to the village, which has been utilized since time immemorial. From the late 1780's into the early 1900's, many people moved to this location to get medical care after epidemic diseases like small pox, measles, tuberculosis and influenza drastically reduced the population by an estimated 75%. Over the years, many more people moved to t̓ɩšosəm after they were forcibly removed from multiple other village sites throughout the territory (information provided by Tla'amin Nation, 2025).

Source: included with note