Etymology
1. O.E.
þencan "conceive in the mind, think, consider, intend" (past tense
þohte, p.p.
geþoht), probably originally "cause to appear to oneself," from P.Gmc.
*thankjan (cf. O.Fris.
thinka, O.S.
thenkian, O.H.G.
denchen, Ger.
denken, O.N.
þekkja, Goth.
þagkjan); O.E.
þencan is the causative form of the distinct O.E. verb
þyncan "to seem or appear" (past tense
þuhte, pp.
geþuht), from P.Gmc.
*thunkjan (cf. Ger.
dünken,
däuchte). Both are from PIE
*tong- "to think, feel" which also is the root of thought and thank. The two meanings converged in M.E. and
þyncan "to seem" was absorbed, except for archaic methinks "it seems to me." Jocular pp.
thunk (not historical, but by analogy of drink, sink, etc.) is recorded from 1876.
Think-tank is 1959 as "research institute" (first ref. is to Center for Behavioral Sciences, Palo Alto, Calif.); it had been colloquial for "the brain" since 1905.
2. Etymology tree
3. Proto-Indo-European *teng-der.
4. Proto-Germanic *þankijaną
5. Proto-West Germanic *þankijan
6. Old English þenċan
7. Middle English thinken
8. English think
9. From Middle English thinken, thynken, thenken, thenchen, from Old English þenċan, from Proto-West Germanic *þankijan, from Proto-Germanic *þankijaną (“to think”), from Proto-Indo-European *teng- (“to think, feel, know”).
10. Cognate with Scots think, thynk (“to think”), North Frisian teenk, taanke, tanke, tånke (“to think”), Saterland Frisian toanke (“to think”), West Frisian tinke (“to think”), Dutch denken, dinken (“to think”), Afrikaans dink (“to think”), Low German denken, dinken (“to think”), German denken (“to think”), Danish tænke (“to think”), Swedish tänka (“to think”), Norwegian Bokmål tenke (“to think”), Norwegian Nynorsk tenkja (“to think”), Icelandic þekkja (“to know, recognise, identify, perceive”), Gothic þagkjan (“to think”), Latin tongeō (“know”). See: Middle English '
thinken', Proto-Germanic '
*þankijaną', Scots '
think', Frisian, Saterlandic 'toanke', Dutch '
denken', Afrikaans '
dink', Low Saxon 'denken', German, old spelling '
denken', Danish '
tænke', Swedish '
tänka', Norwegian '
tenke', Norwegian, nynorsk '
tenkja', Icelandic '
þekkja', Gothic '
þagkjan', Latin '
tongeō'.
Verbs referencing "think"
German, old spelling
denken, Tok Pisin ting, Naija
tink, Low Saxon dünken, Alemannic German
tenke, German, Pennsylvania
denke, Norwegian, nynorsk
tenkja, Tok Pisin tingting, Danish
tykkes, Cimbrian dénkhan, Alemannic German
dänke.