GC: n

S: NCBI – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4241729/ (last access: 20 June 2021); NHS – https://www.nhs.uk/conditions/antibiotics/antibiotic-antimicrobial-resistance/ (last access: 20 June 2021).

N: 1. “line of descent, lineage, breed, ancestry,” c. 1200, from Old English strion, streon “a gain, acquisition, treasure; a begetting, procreation,” from Proto-Germanic *streu-nam- “to pile up,” from PIE *streu-, extended form of root *stere- “to spread.”
Hence “race, stock, line” (early 14c.). Applied to animal species from c. 1600; usually involving fairly minor variations, but not distinct from breed (n.). Normal sound development would have yielded *streen, but the word was altered in late Middle English, apparently by influence of strain (n.1: “injury caused by straining,” c. 1400, from strain (v.)).
2. Microbiology and Parasitology; Genetics: A sub-group of a virus species having specific genetic characteristics.
Phraseology: dominant virus strain, original virus strain, reference virus strain.
3. Evolution (Biology); Genetics: A group of individuals derived by descent from a single individual within a species.

S: 1. OED – https://www.etymonline.com/search?q=strain (last access: 20 June 2021). 2&3. TERMIUM PLUS – https://www.btb.termiumplus.gc.ca/tpv2alpha/alpha-eng.html?lang=eng&i=1&srchtxt=strain&codom2nd_wet=1#resultrecs (last access: 20 June 2021).

SYN: virus strain, viral strain. (depending on context)

S: TERMIUM PLUS – https://www.btb.termiumplus.gc.ca/tpv2alpha/alpha-eng.html?lang=eng&i=1&srchtxt=strain&codom2nd_wet=1#resultrecs (last access: 20 June 2021); GDT – http://gdt.oqlf.gouv.qc.ca/ficheOqlf.aspx?Id_Fiche=26558172 (last access: 20 June 2021).

CR: bacterium, cell strain, disease, virus.