Breathing is an essential part of life, and the term 'breathe in' refers to the act of inhaling AIR. The crossword solutions for this term include INHALE (6 letters), INSPIRE (7 letters), PANT (4 letters), GASP (4 letters), ASPIRATE (8 letters), AIR (3 letters), and RESPIRE (7 letters). INHALE and INSPIRE refer to the act of drawing AIR into the lungs, PANT and GASP are both short, rapid breaths, aspirate is the act of inhaling a substance, AIR is the substance being inhaled, and RESPIRE is the act of breathing out.