"capable of being contaminated," 1847, from Late Latin contaminabilis, from Latin contaminare "to defile, to corrupt, to deteriorate by mingling," originally "to bring into contact," from contamen "contact; pollution," from assimilated form of com "with, together" (see con-) + base of tangere "to touch" (from PIE root *tag- "to touch, handle").
late 14c., "contaminating or contaminated, containing contagion" (of air, water, etc.); "communicable" (of disease); also "morally corrupting," from Old French contagieus (Modern French contagieux) and directly from Late Latin contagiosus, from Latin contagio "a touching, contact," often in a bad sense, "a contact with something physically or morally unclean, contagion," from contingere "to touch," from assimilated form of com "with, together" (see con-) + tangere "to touch," from PIE root *tag- "to touch, handle." Figuratively applied to anything apt to spread from one to another (rumor, etc.) from 1650s. Related: Contagiously; contagiousness.
early 15c., "infect with a disease, defile," from Latin contaminatus, past participle of contaminare "to defile, to corrupt, to deteriorate by mingling," originally "to bring into contact," from contamen "contact; pollution," from assimilated form of com "with, together" (see con-) + *tag-, base of tangere "to touch" (from PIE root *tag- "to touch, handle"). Related: Contaminant (1934).
"act of touching, feeling by the sense of touch," late 15c. (Caxton), from French palpation, from Latin palpationem (nominative palpatio) "a stroking; flattering, flattery," noun of action from past-participle stem of palpare "to touch" (see palpable). Used in English in literal sense.
1580s, "capable of being touched," from French tangible and directly from Late Latin tangibilis "that may be touched," from Latin tangere "to touch," from PIE root *tag- "to touch, handle." Sense of "material" (as in tangible reward) is first recorded 1610s; that of "able to be realized or dealt with" is from 1709. Related: Tangibly.
"a whole number" (as opposed to a fraction), 1570s, from noun use of Latin integer (adj.) "intact, whole, complete," figuratively, "untainted, upright," literally "untouched," from in- "not" (see in- (1)) + root of tangere "to touch" (from PIE root *tag- "to touch, handle"). The word was used earlier in English as an adjective in the Latin sense, "whole, entire" (c. 1500).
"children's game," 1738 (in reference to "Queen Mary's reign"), perhaps a variation of Scottish tig "touch, tap" (1721), probably an alteration of Middle English tek "touch, tap" (see tick (n.2)). Baseball sense is from 1912. It's not an acronym and doesn't stand for anything.