photoperiodism

noun 0.868

daylength

noun 0.671

photophase

noun 0.627

photomorphogenesis

noun 0.607

time of day

noun 0.604

chronobiology

noun 0.602

circadian rhythm

noun 0.600

photobiology

noun 0.594

solar day

noun 0.593

phenology

noun 0.590

light therapy

noun 0.586

phototropism

noun 0.583

photopigment

noun 0.577

photosystem

noun 0.576

diurnal

noun 0.571

photoreception

noun 0.571

period

noun 0.570

photocell

noun 0.569

phytochrome

noun 0.565

photosensor

noun 0.564

photodiode

noun 0.562

photosynthesis

noun 0.557

phototherapy

noun 0.557

photoreceptor

noun 0.554

phototroph

noun 0.553

photometer

noun 0.552

solar calendar

noun 0.550

photoresistor

noun 0.550

lunar phase

noun 0.549

photovoltage

noun 0.548

photochemistry

noun 0.547

solar year

noun 0.546

daytime

noun 0.546

phototransistor

noun 0.543

photochemical

noun 0.543

time of year

noun 0.542

phototype

noun 0.542

solar time

noun 0.541

daylight

noun 0.539

photolysis

noun 0.538

phototransduction

noun 0.538

photosensitivity

noun 0.538

photocurrent

noun 0.538

seasonality

noun 0.538

chronotherapy

noun 0.536

photoinhibition

noun 0.535

periodicity

noun 0.533

daylight saving time

noun 0.533

phototaxis

noun 0.533

nighttime

noun 0.532

photodetector

noun 0.531

photoprint

noun 0.529

photometry

noun 0.528

seasonal affective disorder

noun 0.526

photodermatitis

noun 0.525

grow light

noun 0.521

sleep schedule

noun 0.521

photoprotection

noun 0.521

photoreaction

noun 0.520

photic zone

noun 0.519

periodical

noun 0.519

photophobia

noun 0.518

photovoltaics

noun 0.517

time zone

noun 0.516

photopolymer

noun 0.516

seasonal

noun 0.515

photoreactivity

noun 0.514

photoresponse

noun 0.514

melatonin

noun 0.514

solar

noun 0.513

seasonal depression

noun 0.513

sidereal year

noun 0.513

sunlight

noun 0.511

photophore

noun 0.511

menstrual cycle

noun 0.510

daypart

noun 0.509

solstice

noun 0.509

photoelectric cell

noun 0.509

light curve

noun 0.508

photosensitization

noun 0.508

periodization

noun 0.506

wavelength

noun 0.503

photochromism

noun 0.503

photoaging

noun 0.502

synodic month

noun 0.502

photodegradation

noun 0.501

phytohormone

noun 0.500