self

Etymology

From Middle English self, silf, sulf, from Old English self, seolf, sylf, from Proto-Germanic *selbaz. Cognates include Gothic 𐍃𐌹𐌻𐌱𐌰 (silba), German selbst and Dutch zelf.

pron

1. (obsolete) Himself, herself, itself, themselves; that specific (person mentioned).
   This argument was put forward by the defendant self.
   Now that I put on my glasses I could see that the hut was empty but for our two selves; that it must have been absolutely empty till we entered. 18 Jul 1898, The Leader, Melbourne, page 34, column 1
2. (commercial or humorous) Myself.
   I made out a cheque, payable to self, which cheered me up somewhat.

noun

1. One individual's personality, character, demeanor, or disposition.
   one's true self; one's better self; one's former self
2. The subject of one's own experience of phenomena: perception, emotions, thoughts.
3. An individual person as the object of the person's own reflective consciousness (plural selves).
4. Self-interest or personal advantage.
5. Identity or personality.
6. (botany) A seedling produced by self-pollination (plural selfs).
7. (botany) A flower having its colour uniform as opposed to variegated.
8. (molecular biology, immunology) Any molecule, cell, or tissue of an organism's own (belonging to the self), as opposed to a foreign (nonself) molecule, cell, or tissue (for example, infective, allogenic, or xenogenic).
   Similarity profiles between helper T cell epitopes (of self or microbial antigens and allergens) and human or microbial SWISSPROT collections were produced. For each antigen, both collections yielded largely overlapping profiles, demonstrating that self-nonself discrimination does not rely on qualitative features that distinguish human from microbial peptides. … Epitopes (on self and nonself antigens) can cross-stimulate T cells at increasing potency as their similarity with nonself augments. 2000, G Ristori et al., “Compositional bias and mimicry toward the nonself proteome in immunodominant T cell epitopes of self and nonself antigens”, in FASEB Journal: the official journal of the Federation of American Societies for Experimental Biology, volume 14, number 3, →PMID, pages 431–438
   In plants, the ability to recognize self from nonself plays an important role in fertilization, because self-fertilization will result in less diverse offspring than fertilization with pollen from another individual. 2013 May-June, Katrina G. Claw, “Rapid Evolution in Eggs and Sperm”, in American Scientist, volume 101, number 3

verb

1. (botany) To fertilize by the same individual; to self-fertilize or self-pollinate.
2. (botany) To fertilize by the same strain; to inbreed.

adj

1. Having its own or a single nature or character throughout, as in colour, composition, etc., without addition or change; of the same kind; unmixed.
   a self bow: one made from a single piece of wood
   a self flower or plant: one which is wholly of one colour
2. (obsolete) Same, identical.
3. (obsolete) Belonging to oneself; own.
4. (molecular biology, immunology) Of or relating to any molecule, cell, or tissue of an organism's own (belonging to the self), as opposed to a foreign (nonself) molecule, cell, or tissue (for example, infective, allogenic, or xenogenic).
   Similarity profiles between helper T cell epitopes (of self or microbial antigens and allergens) and human or microbial SWISSPROT collections were produced. For each antigen, both collections yielded largely overlapping profiles, demonstrating that self-nonself discrimination does not rely on qualitative features that distinguish human from microbial peptides. However, epitopes whose probability of mimicry with self or nonself prevails are, respectively, tolerated or immunodominant and coexist within the same (auto-)antigen regardless of its self/nonself nature. Epitopes (on self and nonself antigens) can cross-stimulate T cells at increasing potency as their similarity with nonself augments. 2000, G Ristori et al., “Compositional bias and mimicry toward the nonself proteome in immunodominant T cell epitopes of self and nonself antigens”, in FASEB Journal: the official journal of the Federation of American Societies for Experimental Biology, volume 14, number 3, →PMID, pages 431–438