Of a substance: to initiate (a chemical change) by absorbing light energy and transferring it to a reactant.
To make photosensitive.

Connections NYT: Hints For Today's Puzzle, Wed, Jan 14

NYT Strands Today - Hints, Spangram & Answers for January 14

Today’s Wordle Answer Jan 14 #1670- NYT Wordle Hints & Updates

Today's NYT Pips Hints & Answers

Today's NYT Capture Hints & Answers

NYT Mini Crossword Answers Today - The Mini for Jan 14 Solved

Connections NYT: Hints For Today's Puzzle, Wed, Jan 14

NYT Strands Today - Hints, Spangram & Answers for January 14

Today’s Wordle Answer Jan 14 #1670- NYT Wordle Hints & Updates

Today's NYT Pips Hints & Answers

Today's NYT Capture Hints & Answers

NYT Mini Crossword Answers Today - The Mini for Jan 14 Solved