(Adds investor quotes and details throughout; updates prices)

* TSX ends down 102.04 points, or 0.5%, at 21,292.96

* Technology falls 2.7%; Shopify ends 8.8% lower

* Materials group declines 1.3%

* Aritzia jumps 18.9%

TORONTO, Jan 13 (Reuters) - Canada's main stock index fell on Thursday as investors grew more nervous about the valuations of high-growth companies ahead of expected interest rate hikes by the U.S. Federal Reserve.

The Toronto Stock Exchange's S&P/TSX composite index ended down 102.04 points, or 0.5%, at 21,292.96, pulling back from its highest closing level in nearly seven weeks the previous day.

Wall Street's major indexes also closed lower as investors took profits, particularly in technology stocks after a three-day rally, while multiple Fed officials were out talking about inflation and interest rate hikes.

"Pressure on yields, pressure on tech and pressure on valuations at least in the short-term is a concern," said Matt Skipp, president of SW8 Asset Management.

"I'd be staying clear of big optimistic growth names trading at wild multiples of revenues."

The Toronto market's technology sector fell 2.7%. It included a 8.8% slide in the shares of Shopify Inc, which started the year with the highest market capitalization on the TSX but has since seen its valuation sink by C$51 billion ($41 billion)to C$167 billion.

The materials group, which includes precious and base metals miners and fertilizer companies, lost 1.3%, while energy was down 0.6% as oil prices gave back some recent gains. U.S. crude oil futures settled 0.6% lower at $82.12 a barrel.

Among the sectors that advanced was consumer discretionary with a 1.9% gain. It was led by fashion retailer Aritzia Inc , which ended 18.9% higher after its quarterly results beat estimates.

Financials, the most heavily weighted sector on the TSX, rose 0.4%.

($1 = 1.2515 Canadian dollars) (Reporting by Fergal Smith; Additional reporting by Anisha Sircar in Bengaluru; Editing by Sandra Maler)